blob: 25c3474f91621ee9c8e9237fc7b54ad4c7dc8655 [file] [log] [blame]
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
package com.google.protobuf;
import com.google.protobuf.Descriptors.Descriptor;
import com.google.protobuf.Descriptors.EnumDescriptor;
import com.google.protobuf.Descriptors.EnumValueDescriptor;
import com.google.protobuf.Descriptors.FieldDescriptor;
import java.io.IOException;
import java.math.BigInteger;
import java.nio.CharBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Provide text parsing and formatting support for proto2 instances.
* The implementation largely follows google/protobuf/text_format.cc.
*
* @author wenboz@google.com Wenbo Zhu
* @author kenton@google.com Kenton Varda
*/
public final class TextFormat {
private TextFormat() {}
private static final Logger logger = Logger.getLogger(TextFormat.class.getName());
/**
* Outputs a textual representation of the Protocol Message supplied into
* the parameter output. (This representation is the new version of the
* classic "ProtocolPrinter" output from the original Protocol Buffer system)
*/
public static void print(
final MessageOrBuilder message, final Appendable output)
throws IOException {
Printer.DEFAULT.print(message, multiLineOutput(output));
}
/** Outputs a textual representation of {@code fields} to {@code output}. */
public static void print(final UnknownFieldSet fields,
final Appendable output)
throws IOException {
Printer.DEFAULT.printUnknownFields(fields, multiLineOutput(output));
}
/**
* Same as {@code print()}, except that non-ASCII characters are not
* escaped.
*/
public static void printUnicode(
final MessageOrBuilder message, final Appendable output)
throws IOException {
Printer.UNICODE.print(message, multiLineOutput(output));
}
/**
* Same as {@code print()}, except that non-ASCII characters are not
* escaped.
*/
public static void printUnicode(final UnknownFieldSet fields,
final Appendable output)
throws IOException {
Printer.UNICODE.printUnknownFields(fields, multiLineOutput(output));
}
/**
* Generates a human readable form of this message, useful for debugging and
* other purposes, with no newline characters.
*/
public static String shortDebugString(final MessageOrBuilder message) {
try {
final StringBuilder text = new StringBuilder();
Printer.DEFAULT.print(message, singleLineOutput(text));
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
/**
* Generates a human readable form of the field, useful for debugging
* and other purposes, with no newline characters.
*/
public static String shortDebugString(final FieldDescriptor field,
final Object value) {
try {
final StringBuilder text = new StringBuilder();
Printer.DEFAULT.printField(field, value, singleLineOutput(text));
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
/**
* Generates a human readable form of the unknown fields, useful for debugging
* and other purposes, with no newline characters.
*/
public static String shortDebugString(final UnknownFieldSet fields) {
try {
final StringBuilder text = new StringBuilder();
Printer.DEFAULT.printUnknownFields(fields, singleLineOutput(text));
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
/**
* Like {@code print()}, but writes directly to a {@code String} and
* returns it.
*/
public static String printToString(final MessageOrBuilder message) {
try {
final StringBuilder text = new StringBuilder();
print(message, text);
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
/**
* Like {@code print()}, but writes directly to a {@code String} and
* returns it.
*/
public static String printToString(final UnknownFieldSet fields) {
try {
final StringBuilder text = new StringBuilder();
print(fields, text);
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
/**
* Same as {@code printToString()}, except that non-ASCII characters
* in string type fields are not escaped in backslash+octals.
*/
public static String printToUnicodeString(final MessageOrBuilder message) {
try {
final StringBuilder text = new StringBuilder();
Printer.UNICODE.print(message, multiLineOutput(text));
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
/**
* Same as {@code printToString()}, except that non-ASCII characters
* in string type fields are not escaped in backslash+octals.
*/
public static String printToUnicodeString(final UnknownFieldSet fields) {
try {
final StringBuilder text = new StringBuilder();
Printer.UNICODE.printUnknownFields(fields, multiLineOutput(text));
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
public static void printField(final FieldDescriptor field,
final Object value,
final Appendable output)
throws IOException {
Printer.DEFAULT.printField(field, value, multiLineOutput(output));
}
public static String printFieldToString(final FieldDescriptor field,
final Object value) {
try {
final StringBuilder text = new StringBuilder();
printField(field, value, text);
return text.toString();
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
/**
* Outputs a unicode textual representation of the value of given field value.
*
* <p>Same as {@code printFieldValue()}, except that non-ASCII characters in string type fields
* are not escaped in backslash+octals.
*
* @param field the descriptor of the field
* @param value the value of the field
* @param output the output to which to append the formatted value
* @throws ClassCastException if the value is not appropriate for the given field descriptor
* @throws IOException if there is an exception writing to the output
*/
public static void printUnicodeFieldValue(
final FieldDescriptor field, final Object value, final Appendable output) throws IOException {
Printer.UNICODE.printFieldValue(field, value, multiLineOutput(output));
}
/**
* Outputs a textual representation of the value of given field value.
*
* @param field the descriptor of the field
* @param value the value of the field
* @param output the output to which to append the formatted value
* @throws ClassCastException if the value is not appropriate for the
* given field descriptor
* @throws IOException if there is an exception writing to the output
*/
public static void printFieldValue(final FieldDescriptor field,
final Object value,
final Appendable output)
throws IOException {
Printer.DEFAULT.printFieldValue(field, value, multiLineOutput(output));
}
/**
* Outputs a textual representation of the value of an unknown field.
*
* @param tag the field's tag number
* @param value the value of the field
* @param output the output to which to append the formatted value
* @throws ClassCastException if the value is not appropriate for the
* given field descriptor
* @throws IOException if there is an exception writing to the output
*/
public static void printUnknownFieldValue(final int tag,
final Object value,
final Appendable output)
throws IOException {
printUnknownFieldValue(tag, value, multiLineOutput(output));
}
private static void printUnknownFieldValue(final int tag,
final Object value,
final TextGenerator generator)
throws IOException {
switch (WireFormat.getTagWireType(tag)) {
case WireFormat.WIRETYPE_VARINT:
generator.print(unsignedToString((Long) value));
break;
case WireFormat.WIRETYPE_FIXED32:
generator.print(
String.format((Locale) null, "0x%08x", (Integer) value));
break;
case WireFormat.WIRETYPE_FIXED64:
generator.print(String.format((Locale) null, "0x%016x", (Long) value));
break;
case WireFormat.WIRETYPE_LENGTH_DELIMITED:
try {
// Try to parse and print the field as an embedded message
UnknownFieldSet message = UnknownFieldSet.parseFrom((ByteString) value);
generator.print("{");
generator.eol();
generator.indent();
Printer.DEFAULT.printUnknownFields(message, generator);
generator.outdent();
generator.print("}");
} catch (InvalidProtocolBufferException e) {
// If not parseable as a message, print as a String
generator.print("\"");
generator.print(escapeBytes((ByteString) value));
generator.print("\"");
}
break;
case WireFormat.WIRETYPE_START_GROUP:
Printer.DEFAULT.printUnknownFields((UnknownFieldSet) value, generator);
break;
default:
throw new IllegalArgumentException("Bad tag: " + tag);
}
}
/** Helper class for converting protobufs to text. */
private static final class Printer {
// Printer instance which escapes non-ASCII characters.
static final Printer DEFAULT = new Printer(true);
// Printer instance which emits Unicode (it still escapes newlines and quotes in strings).
static final Printer UNICODE = new Printer(false);
/** Whether to escape non ASCII characters with backslash and octal. */
private final boolean escapeNonAscii;
private Printer(boolean escapeNonAscii) {
this.escapeNonAscii = escapeNonAscii;
}
private void print(
final MessageOrBuilder message, final TextGenerator generator)
throws IOException {
for (Map.Entry<FieldDescriptor, Object> field
: message.getAllFields().entrySet()) {
printField(field.getKey(), field.getValue(), generator);
}
printUnknownFields(message.getUnknownFields(), generator);
}
private void printField(final FieldDescriptor field, final Object value,
final TextGenerator generator) throws IOException {
if (field.isRepeated()) {
// Repeated field. Print each element.
for (Object element : (List<?>) value) {
printSingleField(field, element, generator);
}
} else {
printSingleField(field, value, generator);
}
}
private void printSingleField(final FieldDescriptor field,
final Object value,
final TextGenerator generator)
throws IOException {
if (field.isExtension()) {
generator.print("[");
// We special-case MessageSet elements for compatibility with proto1.
if (field.getContainingType().getOptions().getMessageSetWireFormat()
&& (field.getType() == FieldDescriptor.Type.MESSAGE)
&& (field.isOptional())
// object equality
&& (field.getExtensionScope() == field.getMessageType())) {
generator.print(field.getMessageType().getFullName());
} else {
generator.print(field.getFullName());
}
generator.print("]");
} else {
if (field.getType() == FieldDescriptor.Type.GROUP) {
// Groups must be serialized with their original capitalization.
generator.print(field.getMessageType().getName());
} else {
generator.print(field.getName());
}
}
if (field.getJavaType() == FieldDescriptor.JavaType.MESSAGE) {
generator.print(" {");
generator.eol();
generator.indent();
} else {
generator.print(": ");
}
printFieldValue(field, value, generator);
if (field.getJavaType() == FieldDescriptor.JavaType.MESSAGE) {
generator.outdent();
generator.print("}");
}
generator.eol();
}
private void printFieldValue(final FieldDescriptor field,
final Object value,
final TextGenerator generator)
throws IOException {
switch (field.getType()) {
case INT32:
case SINT32:
case SFIXED32:
generator.print(((Integer) value).toString());
break;
case INT64:
case SINT64:
case SFIXED64:
generator.print(((Long) value).toString());
break;
case BOOL:
generator.print(((Boolean) value).toString());
break;
case FLOAT:
generator.print(((Float) value).toString());
break;
case DOUBLE:
generator.print(((Double) value).toString());
break;
case UINT32:
case FIXED32:
generator.print(unsignedToString((Integer) value));
break;
case UINT64:
case FIXED64:
generator.print(unsignedToString((Long) value));
break;
case STRING:
generator.print("\"");
generator.print(escapeNonAscii
? TextFormatEscaper.escapeText((String) value)
: escapeDoubleQuotesAndBackslashes((String) value)
.replace("\n", "\\n"));
generator.print("\"");
break;
case BYTES:
generator.print("\"");
if (value instanceof ByteString) {
generator.print(escapeBytes((ByteString) value));
} else {
generator.print(escapeBytes((byte[]) value));
}
generator.print("\"");
break;
case ENUM:
generator.print(((EnumValueDescriptor) value).getName());
break;
case MESSAGE:
case GROUP:
print((Message) value, generator);
break;
}
}
private void printUnknownFields(final UnknownFieldSet unknownFields,
final TextGenerator generator)
throws IOException {
for (Map.Entry<Integer, UnknownFieldSet.Field> entry :
unknownFields.asMap().entrySet()) {
final int number = entry.getKey();
final UnknownFieldSet.Field field = entry.getValue();
printUnknownField(number, WireFormat.WIRETYPE_VARINT,
field.getVarintList(), generator);
printUnknownField(number, WireFormat.WIRETYPE_FIXED32,
field.getFixed32List(), generator);
printUnknownField(number, WireFormat.WIRETYPE_FIXED64,
field.getFixed64List(), generator);
printUnknownField(number, WireFormat.WIRETYPE_LENGTH_DELIMITED,
field.getLengthDelimitedList(), generator);
for (final UnknownFieldSet value : field.getGroupList()) {
generator.print(entry.getKey().toString());
generator.print(" {");
generator.eol();
generator.indent();
printUnknownFields(value, generator);
generator.outdent();
generator.print("}");
generator.eol();
}
}
}
private void printUnknownField(final int number,
final int wireType,
final List<?> values,
final TextGenerator generator)
throws IOException {
for (final Object value : values) {
generator.print(String.valueOf(number));
generator.print(": ");
printUnknownFieldValue(wireType, value, generator);
generator.eol();
}
}
}
/** Convert an unsigned 32-bit integer to a string. */
public static String unsignedToString(final int value) {
if (value >= 0) {
return Integer.toString(value);
} else {
return Long.toString(value & 0x00000000FFFFFFFFL);
}
}
/** Convert an unsigned 64-bit integer to a string. */
public static String unsignedToString(final long value) {
if (value >= 0) {
return Long.toString(value);
} else {
// Pull off the most-significant bit so that BigInteger doesn't think
// the number is negative, then set it again using setBit().
return BigInteger.valueOf(value & 0x7FFFFFFFFFFFFFFFL)
.setBit(63).toString();
}
}
private static TextGenerator multiLineOutput(Appendable output) {
return new TextGenerator(output, false);
}
private static TextGenerator singleLineOutput(Appendable output) {
return new TextGenerator(output, true);
}
/**
* An inner class for writing text to the output stream.
*/
private static final class TextGenerator {
private final Appendable output;
private final StringBuilder indent = new StringBuilder();
private final boolean singleLineMode;
// While technically we are "at the start of a line" at the very beginning of the output, all
// we would do in response to this is emit the (zero length) indentation, so it has no effect.
// Setting it false here does however suppress an unwanted leading space in single-line mode.
private boolean atStartOfLine = false;
private TextGenerator(final Appendable output, boolean singleLineMode) {
this.output = output;
this.singleLineMode = singleLineMode;
}
/**
* Indent text by two spaces. After calling Indent(), two spaces will be
* inserted at the beginning of each line of text. Indent() may be called
* multiple times to produce deeper indents.
*/
public void indent() {
indent.append(" ");
}
/**
* Reduces the current indent level by two spaces, or crashes if the indent
* level is zero.
*/
public void outdent() {
final int length = indent.length();
if (length == 0) {
throw new IllegalArgumentException(
" Outdent() without matching Indent().");
}
indent.setLength(length - 2);
}
/**
* Print text to the output stream. Bare newlines are never expected to be passed to this
* method; to indicate the end of a line, call "eol()".
*/
public void print(final CharSequence text) throws IOException {
if (atStartOfLine) {
atStartOfLine = false;
output.append(singleLineMode ? " " : indent);
}
output.append(text);
}
/**
* Signifies reaching the "end of the current line" in the output. In single-line mode, this
* does not result in a newline being emitted, but ensures that a separating space is written
* before the next output.
*/
public void eol() throws IOException {
if (!singleLineMode) {
output.append("\n");
}
atStartOfLine = true;
}
}
// =================================================================
// Parsing
/**
* Represents a stream of tokens parsed from a {@code String}.
*
* <p>The Java standard library provides many classes that you might think
* would be useful for implementing this, but aren't. For example:
*
* <ul>
* <li>{@code java.io.StreamTokenizer}: This almost does what we want -- or,
* at least, something that would get us close to what we want -- except
* for one fatal flaw: It automatically un-escapes strings using Java
* escape sequences, which do not include all the escape sequences we
* need to support (e.g. '\x').
* <li>{@code java.util.Scanner}: This seems like a great way at least to
* parse regular expressions out of a stream (so we wouldn't have to load
* the entire input into a single string before parsing). Sadly,
* {@code Scanner} requires that tokens be delimited with some delimiter.
* Thus, although the text "foo:" should parse to two tokens ("foo" and
* ":"), {@code Scanner} would recognize it only as a single token.
* Furthermore, {@code Scanner} provides no way to inspect the contents
* of delimiters, making it impossible to keep track of line and column
* numbers.
* </ul>
*
* <p>Luckily, Java's regular expression support does manage to be useful to
* us. (Barely: We need {@code Matcher.usePattern()}, which is new in
* Java 1.5.) So, we can use that, at least. Unfortunately, this implies
* that we need to have the entire input in one contiguous string.
*/
private static final class Tokenizer {
private final CharSequence text;
private final Matcher matcher;
private String currentToken;
// The character index within this.text at which the current token begins.
private int pos = 0;
// The line and column numbers of the current token.
private int line = 0;
private int column = 0;
// The line and column numbers of the previous token (allows throwing
// errors *after* consuming).
private int previousLine = 0;
private int previousColumn = 0;
// We use possessive quantifiers (*+ and ++) because otherwise the Java
// regex matcher has stack overflows on large inputs.
private static final Pattern WHITESPACE =
Pattern.compile("(\\s|(#.*$))++", Pattern.MULTILINE);
private static final Pattern TOKEN = Pattern.compile(
"[a-zA-Z_][0-9a-zA-Z_+-]*+|" + // an identifier
"[.]?[0-9+-][0-9a-zA-Z_.+-]*+|" + // a number
"\"([^\"\n\\\\]|\\\\.)*+(\"|\\\\?$)|" + // a double-quoted string
"\'([^\'\n\\\\]|\\\\.)*+(\'|\\\\?$)", // a single-quoted string
Pattern.MULTILINE);
private static final Pattern DOUBLE_INFINITY = Pattern.compile(
"-?inf(inity)?",
Pattern.CASE_INSENSITIVE);
private static final Pattern FLOAT_INFINITY = Pattern.compile(
"-?inf(inity)?f?",
Pattern.CASE_INSENSITIVE);
private static final Pattern FLOAT_NAN = Pattern.compile(
"nanf?",
Pattern.CASE_INSENSITIVE);
/** Construct a tokenizer that parses tokens from the given text. */
private Tokenizer(final CharSequence text) {
this.text = text;
this.matcher = WHITESPACE.matcher(text);
skipWhitespace();
nextToken();
}
int getPreviousLine() {
return previousLine;
}
int getPreviousColumn() {
return previousColumn;
}
int getLine() {
return line;
}
int getColumn() {
return column;
}
/** Are we at the end of the input? */
public boolean atEnd() {
return currentToken.length() == 0;
}
/** Advance to the next token. */
public void nextToken() {
previousLine = line;
previousColumn = column;
// Advance the line counter to the current position.
while (pos < matcher.regionStart()) {
if (text.charAt(pos) == '\n') {
++line;
column = 0;
} else {
++column;
}
++pos;
}
// Match the next token.
if (matcher.regionStart() == matcher.regionEnd()) {
// EOF
currentToken = "";
} else {
matcher.usePattern(TOKEN);
if (matcher.lookingAt()) {
currentToken = matcher.group();
matcher.region(matcher.end(), matcher.regionEnd());
} else {
// Take one character.
currentToken = String.valueOf(text.charAt(pos));
matcher.region(pos + 1, matcher.regionEnd());
}
skipWhitespace();
}
}
/**
* Skip over any whitespace so that the matcher region starts at the next
* token.
*/
private void skipWhitespace() {
matcher.usePattern(WHITESPACE);
if (matcher.lookingAt()) {
matcher.region(matcher.end(), matcher.regionEnd());
}
}
/**
* If the next token exactly matches {@code token}, consume it and return
* {@code true}. Otherwise, return {@code false} without doing anything.
*/
public boolean tryConsume(final String token) {
if (currentToken.equals(token)) {
nextToken();
return true;
} else {
return false;
}
}
/**
* If the next token exactly matches {@code token}, consume it. Otherwise,
* throw a {@link ParseException}.
*/
public void consume(final String token) throws ParseException {
if (!tryConsume(token)) {
throw parseException("Expected \"" + token + "\".");
}
}
/**
* Returns {@code true} if the next token is an integer, but does
* not consume it.
*/
public boolean lookingAtInteger() {
if (currentToken.length() == 0) {
return false;
}
final char c = currentToken.charAt(0);
return ('0' <= c && c <= '9')
|| c == '-' || c == '+';
}
/**
* Returns {@code true} if the current token's text is equal to that
* specified.
*/
public boolean lookingAt(String text) {
return currentToken.equals(text);
}
/**
* If the next token is an identifier, consume it and return its value.
* Otherwise, throw a {@link ParseException}.
*/
public String consumeIdentifier() throws ParseException {
for (int i = 0; i < currentToken.length(); i++) {
final char c = currentToken.charAt(i);
if (('a' <= c && c <= 'z')
|| ('A' <= c && c <= 'Z')
|| ('0' <= c && c <= '9')
|| (c == '_') || (c == '.')) {
// OK
} else {
throw parseException(
"Expected identifier. Found '" + currentToken + "'");
}
}
final String result = currentToken;
nextToken();
return result;
}
/**
* If the next token is an identifier, consume it and return {@code true}.
* Otherwise, return {@code false} without doing anything.
*/
public boolean tryConsumeIdentifier() {
try {
consumeIdentifier();
return true;
} catch (ParseException e) {
return false;
}
}
/**
* If the next token is a 32-bit signed integer, consume it and return its
* value. Otherwise, throw a {@link ParseException}.
*/
public int consumeInt32() throws ParseException {
try {
final int result = parseInt32(currentToken);
nextToken();
return result;
} catch (NumberFormatException e) {
throw integerParseException(e);
}
}
/**
* If the next token is a 32-bit unsigned integer, consume it and return its
* value. Otherwise, throw a {@link ParseException}.
*/
public int consumeUInt32() throws ParseException {
try {
final int result = parseUInt32(currentToken);
nextToken();
return result;
} catch (NumberFormatException e) {
throw integerParseException(e);
}
}
/**
* If the next token is a 64-bit signed integer, consume it and return its
* value. Otherwise, throw a {@link ParseException}.
*/
public long consumeInt64() throws ParseException {
try {
final long result = parseInt64(currentToken);
nextToken();
return result;
} catch (NumberFormatException e) {
throw integerParseException(e);
}
}
/**
* If the next token is a 64-bit signed integer, consume it and return
* {@code true}. Otherwise, return {@code false} without doing anything.
*/
public boolean tryConsumeInt64() {
try {
consumeInt64();
return true;
} catch (ParseException e) {
return false;
}
}
/**
* If the next token is a 64-bit unsigned integer, consume it and return its
* value. Otherwise, throw a {@link ParseException}.
*/
public long consumeUInt64() throws ParseException {
try {
final long result = parseUInt64(currentToken);
nextToken();
return result;
} catch (NumberFormatException e) {
throw integerParseException(e);
}
}
/**
* If the next token is a 64-bit unsigned integer, consume it and return
* {@code true}. Otherwise, return {@code false} without doing anything.
*/
public boolean tryConsumeUInt64() {
try {
consumeUInt64();
return true;
} catch (ParseException e) {
return false;
}
}
/**
* If the next token is a double, consume it and return its value.
* Otherwise, throw a {@link ParseException}.
*/
public double consumeDouble() throws ParseException {
// We need to parse infinity and nan separately because
// Double.parseDouble() does not accept "inf", "infinity", or "nan".
if (DOUBLE_INFINITY.matcher(currentToken).matches()) {
final boolean negative = currentToken.startsWith("-");
nextToken();
return negative ? Double.NEGATIVE_INFINITY : Double.POSITIVE_INFINITY;
}
if (currentToken.equalsIgnoreCase("nan")) {
nextToken();
return Double.NaN;
}
try {
final double result = Double.parseDouble(currentToken);
nextToken();
return result;
} catch (NumberFormatException e) {
throw floatParseException(e);
}
}
/**
* If the next token is a double, consume it and return {@code true}.
* Otherwise, return {@code false} without doing anything.
*/
public boolean tryConsumeDouble() {
try {
consumeDouble();
return true;
} catch (ParseException e) {
return false;
}
}
/**
* If the next token is a float, consume it and return its value.
* Otherwise, throw a {@link ParseException}.
*/
public float consumeFloat() throws ParseException {
// We need to parse infinity and nan separately because
// Float.parseFloat() does not accept "inf", "infinity", or "nan".
if (FLOAT_INFINITY.matcher(currentToken).matches()) {
final boolean negative = currentToken.startsWith("-");
nextToken();
return negative ? Float.NEGATIVE_INFINITY : Float.POSITIVE_INFINITY;
}
if (FLOAT_NAN.matcher(currentToken).matches()) {
nextToken();
return Float.NaN;
}
try {
final float result = Float.parseFloat(currentToken);
nextToken();
return result;
} catch (NumberFormatException e) {
throw floatParseException(e);
}
}
/**
* If the next token is a float, consume it and return {@code true}.
* Otherwise, return {@code false} without doing anything.
*/
public boolean tryConsumeFloat() {
try {
consumeFloat();
return true;
} catch (ParseException e) {
return false;
}
}
/**
* If the next token is a boolean, consume it and return its value.
* Otherwise, throw a {@link ParseException}.
*/
public boolean consumeBoolean() throws ParseException {
if (currentToken.equals("true")
|| currentToken.equals("True")
|| currentToken.equals("t")
|| currentToken.equals("1")) {
nextToken();
return true;
} else if (currentToken.equals("false")
|| currentToken.equals("False")
|| currentToken.equals("f")
|| currentToken.equals("0")) {
nextToken();
return false;
} else {
throw parseException("Expected \"true\" or \"false\". Found \"" + currentToken + "\".");
}
}
/**
* If the next token is a string, consume it and return its (unescaped)
* value. Otherwise, throw a {@link ParseException}.
*/
public String consumeString() throws ParseException {
return consumeByteString().toStringUtf8();
}
/**
* If the next token is a string, consume it and return true. Otherwise,
* return false.
*/
public boolean tryConsumeString() {
try {
consumeString();
return true;
} catch (ParseException e) {
return false;
}
}
/**
* If the next token is a string, consume it, unescape it as a
* {@link ByteString}, and return it. Otherwise, throw a
* {@link ParseException}.
*/
public ByteString consumeByteString() throws ParseException {
List<ByteString> list = new ArrayList<ByteString>();
consumeByteString(list);
while (currentToken.startsWith("'") || currentToken.startsWith("\"")) {
consumeByteString(list);
}
return ByteString.copyFrom(list);
}
/**
* Like {@link #consumeByteString()} but adds each token of the string to
* the given list. String literals (whether bytes or text) may come in
* multiple adjacent tokens which are automatically concatenated, like in
* C or Python.
*/
private void consumeByteString(List<ByteString> list)
throws ParseException {
final char quote = currentToken.length() > 0
? currentToken.charAt(0)
: '\0';
if (quote != '\"' && quote != '\'') {
throw parseException("Expected string.");
}
if (currentToken.length() < 2
|| currentToken.charAt(currentToken.length() - 1) != quote) {
throw parseException("String missing ending quote.");
}
try {
final String escaped =
currentToken.substring(1, currentToken.length() - 1);
final ByteString result = unescapeBytes(escaped);
nextToken();
list.add(result);
} catch (InvalidEscapeSequenceException e) {
throw parseException(e.getMessage());
}
}
/**
* Returns a {@link ParseException} with the current line and column
* numbers in the description, suitable for throwing.
*/
public ParseException parseException(final String description) {
// Note: People generally prefer one-based line and column numbers.
return new ParseException(
line + 1, column + 1, description);
}
/**
* Returns a {@link ParseException} with the line and column numbers of
* the previous token in the description, suitable for throwing.
*/
public ParseException parseExceptionPreviousToken(
final String description) {
// Note: People generally prefer one-based line and column numbers.
return new ParseException(
previousLine + 1, previousColumn + 1, description);
}
/**
* Constructs an appropriate {@link ParseException} for the given
* {@code NumberFormatException} when trying to parse an integer.
*/
private ParseException integerParseException(
final NumberFormatException e) {
return parseException("Couldn't parse integer: " + e.getMessage());
}
/**
* Constructs an appropriate {@link ParseException} for the given
* {@code NumberFormatException} when trying to parse a float or double.
*/
private ParseException floatParseException(final NumberFormatException e) {
return parseException("Couldn't parse number: " + e.getMessage());
}
/**
* Returns a {@link UnknownFieldParseException} with the line and column
* numbers of the previous token in the description, and the unknown field
* name, suitable for throwing.
*/
public UnknownFieldParseException unknownFieldParseExceptionPreviousToken(
final String unknownField, final String description) {
// Note: People generally prefer one-based line and column numbers.
return new UnknownFieldParseException(
previousLine + 1, previousColumn + 1, unknownField, description);
}
}
/** Thrown when parsing an invalid text format message. */
public static class ParseException extends IOException {
private static final long serialVersionUID = 3196188060225107702L;
private final int line;
private final int column;
/** Create a new instance, with -1 as the line and column numbers. */
public ParseException(final String message) {
this(-1, -1, message);
}
/**
* Create a new instance
*
* @param line the line number where the parse error occurred,
* using 1-offset.
* @param column the column number where the parser error occurred,
* using 1-offset.
*/
public ParseException(final int line, final int column,
final String message) {
super(Integer.toString(line) + ":" + column + ": " + message);
this.line = line;
this.column = column;
}
/**
* Return the line where the parse exception occurred, or -1 when
* none is provided. The value is specified as 1-offset, so the first
* line is line 1.
*/
public int getLine() {
return line;
}
/**
* Return the column where the parse exception occurred, or -1 when
* none is provided. The value is specified as 1-offset, so the first
* line is line 1.
*/
public int getColumn() {
return column;
}
}
/**
* Thrown when encountering an unknown field while parsing
* a text format message.
*/
public static class UnknownFieldParseException extends ParseException {
private final String unknownField;
/**
* Create a new instance, with -1 as the line and column numbers, and an
* empty unknown field name.
*/
public UnknownFieldParseException(final String message) {
this(-1, -1, "", message);
}
/**
* Create a new instance
*
* @param line the line number where the parse error occurred,
* using 1-offset.
* @param column the column number where the parser error occurred,
* using 1-offset.
* @param unknownField the name of the unknown field found while parsing.
*/
public UnknownFieldParseException(final int line, final int column,
final String unknownField, final String message) {
super(line, column, message);
this.unknownField = unknownField;
}
/**
* Return the name of the unknown field encountered while parsing the
* protocol buffer string.
*/
public String getUnknownField() {
return unknownField;
}
}
private static final Parser PARSER = Parser.newBuilder().build();
/**
* Return a {@link Parser} instance which can parse text-format
* messages. The returned instance is thread-safe.
*/
public static Parser getParser() {
return PARSER;
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}.
*/
public static void merge(final Readable input,
final Message.Builder builder)
throws IOException {
PARSER.merge(input, builder);
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}.
*/
public static void merge(final CharSequence input,
final Message.Builder builder)
throws ParseException {
PARSER.merge(input, builder);
}
/**
* Parse a text-format message from {@code input}.
*
* @return the parsed message, guaranteed initialized
*/
public static <T extends Message> T parse(final CharSequence input,
final Class<T> protoClass)
throws ParseException {
Message.Builder builder =
Internal.getDefaultInstance(protoClass).newBuilderForType();
merge(input, builder);
@SuppressWarnings("unchecked")
T output = (T) builder.build();
return output;
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}. Extensions will be recognized if they are
* registered in {@code extensionRegistry}.
*/
public static void merge(final Readable input,
final ExtensionRegistry extensionRegistry,
final Message.Builder builder)
throws IOException {
PARSER.merge(input, extensionRegistry, builder);
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}. Extensions will be recognized if they are
* registered in {@code extensionRegistry}.
*/
public static void merge(final CharSequence input,
final ExtensionRegistry extensionRegistry,
final Message.Builder builder)
throws ParseException {
PARSER.merge(input, extensionRegistry, builder);
}
/**
* Parse a text-format message from {@code input}. Extensions will be
* recognized if they are registered in {@code extensionRegistry}.
*
* @return the parsed message, guaranteed initialized
*/
public static <T extends Message> T parse(
final CharSequence input,
final ExtensionRegistry extensionRegistry,
final Class<T> protoClass)
throws ParseException {
Message.Builder builder =
Internal.getDefaultInstance(protoClass).newBuilderForType();
merge(input, extensionRegistry, builder);
@SuppressWarnings("unchecked")
T output = (T) builder.build();
return output;
}
/**
* Parser for text-format proto2 instances. This class is thread-safe.
* The implementation largely follows google/protobuf/text_format.cc.
*
* <p>Use {@link TextFormat#getParser()} to obtain the default parser, or
* {@link Builder} to control the parser behavior.
*/
public static class Parser {
/**
* Determines if repeated values for non-repeated fields and
* oneofs are permitted. For example, given required/optional field "foo"
* and a oneof containing "baz" and "qux":
* <ul>
* <li>"foo: 1 foo: 2"
* <li>"baz: 1 qux: 2"
* <li>merging "foo: 2" into a proto in which foo is already set, or
* <li>merging "qux: 2" into a proto in which baz is already set.
* </ul>
*/
public enum SingularOverwritePolicy {
/** The last value is retained. */
ALLOW_SINGULAR_OVERWRITES,
/** An error is issued. */
FORBID_SINGULAR_OVERWRITES
}
private final boolean allowUnknownFields;
private final boolean allowUnknownEnumValues;
private final SingularOverwritePolicy singularOverwritePolicy;
private TextFormatParseInfoTree.Builder parseInfoTreeBuilder;
private Parser(
boolean allowUnknownFields,
boolean allowUnknownEnumValues,
SingularOverwritePolicy singularOverwritePolicy,
TextFormatParseInfoTree.Builder parseInfoTreeBuilder) {
this.allowUnknownFields = allowUnknownFields;
this.allowUnknownEnumValues = allowUnknownEnumValues;
this.singularOverwritePolicy = singularOverwritePolicy;
this.parseInfoTreeBuilder = parseInfoTreeBuilder;
}
/**
* Returns a new instance of {@link Builder}.
*/
public static Builder newBuilder() {
return new Builder();
}
/**
* Builder that can be used to obtain new instances of {@link Parser}.
*/
public static class Builder {
private boolean allowUnknownFields = false;
private boolean allowUnknownEnumValues = false;
private SingularOverwritePolicy singularOverwritePolicy =
SingularOverwritePolicy.ALLOW_SINGULAR_OVERWRITES;
private TextFormatParseInfoTree.Builder parseInfoTreeBuilder = null;
/**
* Sets parser behavior when a non-repeated field appears more than once.
*/
public Builder setSingularOverwritePolicy(SingularOverwritePolicy p) {
this.singularOverwritePolicy = p;
return this;
}
public Builder setParseInfoTreeBuilder(
TextFormatParseInfoTree.Builder parseInfoTreeBuilder) {
this.parseInfoTreeBuilder = parseInfoTreeBuilder;
return this;
}
public Parser build() {
return new Parser(
allowUnknownFields,
allowUnknownEnumValues,
singularOverwritePolicy,
parseInfoTreeBuilder);
}
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}.
*/
public void merge(final Readable input,
final Message.Builder builder)
throws IOException {
merge(input, ExtensionRegistry.getEmptyRegistry(), builder);
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}.
*/
public void merge(final CharSequence input,
final Message.Builder builder)
throws ParseException {
merge(input, ExtensionRegistry.getEmptyRegistry(), builder);
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}. Extensions will be recognized if they are
* registered in {@code extensionRegistry}.
*/
public void merge(final Readable input,
final ExtensionRegistry extensionRegistry,
final Message.Builder builder)
throws IOException {
// Read the entire input to a String then parse that.
// If StreamTokenizer were not quite so crippled, or if there were a kind
// of Reader that could read in chunks that match some particular regex,
// or if we wanted to write a custom Reader to tokenize our stream, then
// we would not have to read to one big String. Alas, none of these is
// the case. Oh well.
merge(toStringBuilder(input), extensionRegistry, builder);
}
private static final int BUFFER_SIZE = 4096;
// TODO(chrisn): See if working around java.io.Reader#read(CharBuffer)
// overhead is worthwhile
private static StringBuilder toStringBuilder(final Readable input)
throws IOException {
final StringBuilder text = new StringBuilder();
final CharBuffer buffer = CharBuffer.allocate(BUFFER_SIZE);
while (true) {
final int n = input.read(buffer);
if (n == -1) {
break;
}
buffer.flip();
text.append(buffer, 0, n);
}
return text;
}
// Check both unknown fields and unknown extensions and log warning messages
// or throw exceptions according to the flag.
private void checkUnknownFields(final List<String> unknownFields)
throws ParseException {
if (unknownFields.isEmpty()) {
return;
}
StringBuilder msg = new StringBuilder("Input contains unknown fields and/or extensions:");
for (String field : unknownFields) {
msg.append('\n').append(field);
}
if (allowUnknownFields) {
logger.warning(msg.toString());
} else {
String[] lineColumn = unknownFields.get(0).split(":");
throw new ParseException(Integer.valueOf(lineColumn[0]),
Integer.valueOf(lineColumn[1]), msg.toString());
}
}
/**
* Parse a text-format message from {@code input} and merge the contents
* into {@code builder}. Extensions will be recognized if they are
* registered in {@code extensionRegistry}.
*/
public void merge(final CharSequence input,
final ExtensionRegistry extensionRegistry,
final Message.Builder builder)
throws ParseException {
final Tokenizer tokenizer = new Tokenizer(input);
MessageReflection.BuilderAdapter target =
new MessageReflection.BuilderAdapter(builder);
List<String> unknownFields = new ArrayList<String>();
while (!tokenizer.atEnd()) {
mergeField(tokenizer, extensionRegistry, target, unknownFields);
}
checkUnknownFields(unknownFields);
}
/**
* Parse a single field from {@code tokenizer} and merge it into
* {@code builder}.
*/
private void mergeField(final Tokenizer tokenizer,
final ExtensionRegistry extensionRegistry,
final MessageReflection.MergeTarget target,
List<String> unknownFields)
throws ParseException {
mergeField(tokenizer, extensionRegistry, target, parseInfoTreeBuilder,
unknownFields);
}
/**
* Parse a single field from {@code tokenizer} and merge it into
* {@code target}.
*/
private void mergeField(final Tokenizer tokenizer,
final ExtensionRegistry extensionRegistry,
final MessageReflection.MergeTarget target,
TextFormatParseInfoTree.Builder parseTreeBuilder,
List<String> unknownFields)
throws ParseException {
FieldDescriptor field = null;
int startLine = tokenizer.getLine();
int startColumn = tokenizer.getColumn();
final Descriptor type = target.getDescriptorForType();
ExtensionRegistry.ExtensionInfo extension = null;
if (tokenizer.tryConsume("[")) {
// An extension.
final StringBuilder name =
new StringBuilder(tokenizer.consumeIdentifier());
while (tokenizer.tryConsume(".")) {
name.append('.');
name.append(tokenizer.consumeIdentifier());
}
extension = target.findExtensionByName(
extensionRegistry, name.toString());
if (extension == null) {
unknownFields.add(
(tokenizer.getPreviousLine() + 1)
+ ":"
+ (tokenizer.getPreviousColumn() + 1)
+ ":\t"
+ type.getFullName()
+ ".["
+ name
+ "]");
} else {
if (extension.descriptor.getContainingType() != type) {
throw tokenizer.parseExceptionPreviousToken(
"Extension \"" + name + "\" does not extend message type \""
+ type.getFullName() + "\".");
}
field = extension.descriptor;
}
tokenizer.consume("]");
} else {
final String name = tokenizer.consumeIdentifier();
field = type.findFieldByName(name);
// Group names are expected to be capitalized as they appear in the
// .proto file, which actually matches their type names, not their field
// names.
if (field == null) {
// Explicitly specify US locale so that this code does not break when
// executing in Turkey.
final String lowerName = name.toLowerCase(Locale.US);
field = type.findFieldByName(lowerName);
// If the case-insensitive match worked but the field is NOT a group,
if (field != null && field.getType() != FieldDescriptor.Type.GROUP) {
field = null;
}
}
// Again, special-case group names as described above.
if (field != null && field.getType() == FieldDescriptor.Type.GROUP
&& !field.getMessageType().getName().equals(name)) {
field = null;
}
if (field == null) {
unknownFields.add(
(tokenizer.getPreviousLine() + 1)
+ ":"
+ (tokenizer.getPreviousColumn() + 1)
+ ":\t"
+ type.getFullName()
+ "."
+ name);
}
}
// Skips unknown fields.
if (field == null) {
// Try to guess the type of this field.
// If this field is not a message, there should be a ":" between the
// field name and the field value and also the field value should not
// start with "{" or "<" which indicates the beginning of a message body.
// If there is no ":" or there is a "{" or "<" after ":", this field has
// to be a message or the input is ill-formed.
if (tokenizer.tryConsume(":")
&& !tokenizer.lookingAt("{")
&& !tokenizer.lookingAt("<")) {
skipFieldValue(tokenizer);
} else {
skipFieldMessage(tokenizer);
}
return;
}
// Handle potential ':'.
if (field.getJavaType() == FieldDescriptor.JavaType.MESSAGE) {
tokenizer.tryConsume(":"); // optional
if (parseTreeBuilder != null) {
TextFormatParseInfoTree.Builder childParseTreeBuilder =
parseTreeBuilder.getBuilderForSubMessageField(field);
consumeFieldValues(tokenizer, extensionRegistry, target, field, extension,
childParseTreeBuilder, unknownFields);
} else {
consumeFieldValues(tokenizer, extensionRegistry, target, field, extension,
parseTreeBuilder, unknownFields);
}
} else {
tokenizer.consume(":"); // required
consumeFieldValues(tokenizer, extensionRegistry, target, field,
extension, parseTreeBuilder, unknownFields);
}
if (parseTreeBuilder != null) {
parseTreeBuilder.setLocation(
field, TextFormatParseLocation.create(startLine, startColumn));
}
// For historical reasons, fields may optionally be separated by commas or
// semicolons.
if (!tokenizer.tryConsume(";")) {
tokenizer.tryConsume(",");
}
}
/**
* Parse a one or more field values from {@code tokenizer} and merge it into
* {@code builder}.
*/
private void consumeFieldValues(
final Tokenizer tokenizer,
final ExtensionRegistry extensionRegistry,
final MessageReflection.MergeTarget target,
final FieldDescriptor field,
final ExtensionRegistry.ExtensionInfo extension,
final TextFormatParseInfoTree.Builder parseTreeBuilder,
List<String> unknownFields)
throws ParseException {
// Support specifying repeated field values as a comma-separated list.
// Ex."foo: [1, 2, 3]"
if (field.isRepeated() && tokenizer.tryConsume("[")) {
if (!tokenizer.tryConsume("]")) { // Allow "foo: []" to be treated as empty.
while (true) {
consumeFieldValue(
tokenizer,
extensionRegistry,
target,
field,
extension,
parseTreeBuilder,
unknownFields);
if (tokenizer.tryConsume("]")) {
// End of list.
break;
}
tokenizer.consume(",");
}
}
} else {
consumeFieldValue(tokenizer, extensionRegistry, target, field,
extension, parseTreeBuilder, unknownFields);
}
}
/**
* Parse a single field value from {@code tokenizer} and merge it into
* {@code builder}.
*/
private void consumeFieldValue(
final Tokenizer tokenizer,
final ExtensionRegistry extensionRegistry,
final MessageReflection.MergeTarget target,
final FieldDescriptor field,
final ExtensionRegistry.ExtensionInfo extension,
final TextFormatParseInfoTree.Builder parseTreeBuilder,
List<String> unknownFields)
throws ParseException {
Object value = null;
if (field.getJavaType() == FieldDescriptor.JavaType.MESSAGE) {
final String endToken;
if (tokenizer.tryConsume("<")) {
endToken = ">";
} else {
tokenizer.consume("{");
endToken = "}";
}
final MessageReflection.MergeTarget subField;
subField = target.newMergeTargetForField(field,
(extension == null) ? null : extension.defaultInstance);
while (!tokenizer.tryConsume(endToken)) {
if (tokenizer.atEnd()) {
throw tokenizer.parseException(
"Expected \"" + endToken + "\".");
}
mergeField(tokenizer, extensionRegistry, subField, parseTreeBuilder,
unknownFields);
}
value = subField.finish();
} else {
switch (field.getType()) {
case INT32:
case SINT32:
case SFIXED32:
value = tokenizer.consumeInt32();
break;
case INT64:
case SINT64:
case SFIXED64:
value = tokenizer.consumeInt64();
break;
case UINT32:
case FIXED32:
value = tokenizer.consumeUInt32();
break;
case UINT64:
case FIXED64:
value = tokenizer.consumeUInt64();
break;
case FLOAT:
value = tokenizer.consumeFloat();
break;
case DOUBLE:
value = tokenizer.consumeDouble();
break;
case BOOL:
value = tokenizer.consumeBoolean();
break;
case STRING:
value = tokenizer.consumeString();
break;
case BYTES:
value = tokenizer.consumeByteString();
break;
case ENUM:
final EnumDescriptor enumType = field.getEnumType();
if (tokenizer.lookingAtInteger()) {
final int number = tokenizer.consumeInt32();
value = enumType.findValueByNumber(number);
if (value == null) {
String unknownValueMsg =
"Enum type \""
+ enumType.getFullName()
+ "\" has no value with number "
+ number
+ '.';
if (allowUnknownEnumValues) {
logger.warning(unknownValueMsg);
return;
} else {
throw tokenizer.parseExceptionPreviousToken(
"Enum type \""
+ enumType.getFullName()
+ "\" has no value with number "
+ number
+ '.');
}
}
} else {
final String id = tokenizer.consumeIdentifier();
value = enumType.findValueByName(id);
if (value == null) {
String unknownValueMsg =
"Enum type \""
+ enumType.getFullName()
+ "\" has no value named \""
+ id
+ "\".";
if (allowUnknownEnumValues) {
logger.warning(unknownValueMsg);
return;
} else {
throw tokenizer.parseExceptionPreviousToken(unknownValueMsg);
}
}
}
break;
case MESSAGE:
case GROUP:
throw new RuntimeException("Can't get here.");
}
}
if (field.isRepeated()) {
// TODO(b/29122459): If field.isMapField() and FORBID_SINGULAR_OVERWRITES mode,
// check for duplicate map keys here.
target.addRepeatedField(field, value);
} else if ((singularOverwritePolicy
== SingularOverwritePolicy.FORBID_SINGULAR_OVERWRITES)
&& target.hasField(field)) {
throw tokenizer.parseExceptionPreviousToken("Non-repeated field \""
+ field.getFullName() + "\" cannot be overwritten.");
} else if ((singularOverwritePolicy
== SingularOverwritePolicy.FORBID_SINGULAR_OVERWRITES)
&& field.getContainingOneof() != null
&& target.hasOneof(field.getContainingOneof())) {
Descriptors.OneofDescriptor oneof = field.getContainingOneof();
throw tokenizer.parseExceptionPreviousToken("Field \""
+ field.getFullName() + "\" is specified along with field \""
+ target.getOneofFieldDescriptor(oneof).getFullName()
+ "\", another member of oneof \"" + oneof.getName() + "\".");
} else {
target.setField(field, value);
}
}
/**
* Skips the next field including the field's name and value.
*/
private void skipField(Tokenizer tokenizer) throws ParseException {
if (tokenizer.tryConsume("[")) {
// Extension name.
do {
tokenizer.consumeIdentifier();
} while (tokenizer.tryConsume("."));
tokenizer.consume("]");
} else {
tokenizer.consumeIdentifier();
}
// Try to guess the type of this field.
// If this field is not a message, there should be a ":" between the
// field name and the field value and also the field value should not
// start with "{" or "<" which indicates the beginning of a message body.
// If there is no ":" or there is a "{" or "<" after ":", this field has
// to be a message or the input is ill-formed.
if (tokenizer.tryConsume(":")
&& !tokenizer.lookingAt("<")
&& !tokenizer.lookingAt("{")) {
skipFieldValue(tokenizer);
} else {
skipFieldMessage(tokenizer);
}
// For historical reasons, fields may optionally be separated by commas or
// semicolons.
if (!tokenizer.tryConsume(";")) {
tokenizer.tryConsume(",");
}
}
/**
* Skips the whole body of a message including the beginning delimiter and
* the ending delimiter.
*/
private void skipFieldMessage(Tokenizer tokenizer) throws ParseException {
final String delimiter;
if (tokenizer.tryConsume("<")) {
delimiter = ">";
} else {
tokenizer.consume("{");
delimiter = "}";
}
while (!tokenizer.lookingAt(">") && !tokenizer.lookingAt("}")) {
skipField(tokenizer);
}
tokenizer.consume(delimiter);
}
/**
* Skips a field value.
*/
private void skipFieldValue(Tokenizer tokenizer) throws ParseException {
if (tokenizer.tryConsumeString()) {
while (tokenizer.tryConsumeString()) {}
return;
}
if (!tokenizer.tryConsumeIdentifier() // includes enum & boolean
&& !tokenizer.tryConsumeInt64() // includes int32
&& !tokenizer.tryConsumeUInt64() // includes uint32
&& !tokenizer.tryConsumeDouble()
&& !tokenizer.tryConsumeFloat()) {
throw tokenizer.parseException(
"Invalid field value: " + tokenizer.currentToken);
}
}
}
// =================================================================
// Utility functions
//
// Some of these methods are package-private because Descriptors.java uses
// them.
/**
* Escapes bytes in the format used in protocol buffer text format, which
* is the same as the format used for C string literals. All bytes
* that are not printable 7-bit ASCII characters are escaped, as well as
* backslash, single-quote, and double-quote characters. Characters for
* which no defined short-hand escape sequence is defined will be escaped
* using 3-digit octal sequences.
*/
public static String escapeBytes(ByteString input) {
return TextFormatEscaper.escapeBytes(input);
}
/**
* Like {@link #escapeBytes(ByteString)}, but used for byte array.
*/
public static String escapeBytes(byte[] input) {
return TextFormatEscaper.escapeBytes(input);
}
/**
* Un-escape a byte sequence as escaped using
* {@link #escapeBytes(ByteString)}. Two-digit hex escapes (starting with
* "\x") are also recognized.
*/
public static ByteString unescapeBytes(final CharSequence charString)
throws InvalidEscapeSequenceException {
// First convert the Java character sequence to UTF-8 bytes.
ByteString input = ByteString.copyFromUtf8(charString.toString());
// Then unescape certain byte sequences introduced by ASCII '\\'. The valid
// escapes can all be expressed with ASCII characters, so it is safe to
// operate on bytes here.
//
// Unescaping the input byte array will result in a byte sequence that's no
// longer than the input. That's because each escape sequence is between
// two and four bytes long and stands for a single byte.
final byte[] result = new byte[input.size()];
int pos = 0;
for (int i = 0; i < input.size(); i++) {
byte c = input.byteAt(i);
if (c == '\\') {
if (i + 1 < input.size()) {
++i;
c = input.byteAt(i);
if (isOctal(c)) {
// Octal escape.
int code = digitValue(c);
if (i + 1 < input.size() && isOctal(input.byteAt(i + 1))) {
++i;
code = code * 8 + digitValue(input.byteAt(i));
}
if (i + 1 < input.size() && isOctal(input.byteAt(i + 1))) {
++i;
code = code * 8 + digitValue(input.byteAt(i));
}
// TODO: Check that 0 <= code && code <= 0xFF.
result[pos++] = (byte) code;
} else {
switch (c) {
case 'a' : result[pos++] = 0x07; break;
case 'b' : result[pos++] = '\b'; break;
case 'f' : result[pos++] = '\f'; break;
case 'n' : result[pos++] = '\n'; break;
case 'r' : result[pos++] = '\r'; break;
case 't' : result[pos++] = '\t'; break;
case 'v' : result[pos++] = 0x0b; break;
case '\\': result[pos++] = '\\'; break;
case '\'': result[pos++] = '\''; break;
case '"' : result[pos++] = '\"'; break;
case 'x':
// hex escape
int code = 0;
if (i + 1 < input.size() && isHex(input.byteAt(i + 1))) {
++i;
code = digitValue(input.byteAt(i));
} else {
throw new InvalidEscapeSequenceException(
"Invalid escape sequence: '\\x' with no digits");
}
if (i + 1 < input.size() && isHex(input.byteAt(i + 1))) {
++i;
code = code * 16 + digitValue(input.byteAt(i));
}
result[pos++] = (byte) code;
break;
default:
throw new InvalidEscapeSequenceException(
"Invalid escape sequence: '\\" + (char) c + '\'');
}
}
} else {
throw new InvalidEscapeSequenceException(
"Invalid escape sequence: '\\' at end of string.");
}
} else {
result[pos++] = c;
}
}
return result.length == pos
? ByteString.wrap(result) // This reference has not been out of our control.
: ByteString.copyFrom(result, 0, pos);
}
/**
* Thrown by {@link TextFormat#unescapeBytes} and
* {@link TextFormat#unescapeText} when an invalid escape sequence is seen.
*/
public static class InvalidEscapeSequenceException extends IOException {
private static final long serialVersionUID = -8164033650142593304L;
InvalidEscapeSequenceException(final String description) {
super(description);
}
}
/**
* Like {@link #escapeBytes(ByteString)}, but escapes a text string.
* Non-ASCII characters are first encoded as UTF-8, then each byte is escaped
* individually as a 3-digit octal escape. Yes, it's weird.
*/
static String escapeText(final String input) {
return escapeBytes(ByteString.copyFromUtf8(input));
}
/**
* Escape double quotes and backslashes in a String for unicode output of a message.
*/
public static String escapeDoubleQuotesAndBackslashes(final String input) {
return TextFormatEscaper.escapeDoubleQuotesAndBackslashes(input);
}
/**
* Un-escape a text string as escaped using {@link #escapeText(String)}.
* Two-digit hex escapes (starting with "\x") are also recognized.
*/
static String unescapeText(final String input)
throws InvalidEscapeSequenceException {
return unescapeBytes(input).toStringUtf8();
}
/** Is this an octal digit? */
private static boolean isOctal(final byte c) {
return '0' <= c && c <= '7';
}
/** Is this a hex digit? */
private static boolean isHex(final byte c) {
return ('0' <= c && c <= '9')
|| ('a' <= c && c <= 'f')
|| ('A' <= c && c <= 'F');
}
/**
* Interpret a character as a digit (in any base up to 36) and return the
* numeric value. This is like {@code Character.digit()} but we don't accept
* non-ASCII digits.
*/
private static int digitValue(final byte c) {
if ('0' <= c && c <= '9') {
return c - '0';
} else if ('a' <= c && c <= 'z') {
return c - 'a' + 10;
} else {
return c - 'A' + 10;
}
}
/**
* Parse a 32-bit signed integer from the text. Unlike the Java standard
* {@code Integer.parseInt()}, this function recognizes the prefixes "0x"
* and "0" to signify hexadecimal and octal numbers, respectively.
*/
static int parseInt32(final String text) throws NumberFormatException {
return (int) parseInteger(text, true, false);
}
/**
* Parse a 32-bit unsigned integer from the text. Unlike the Java standard
* {@code Integer.parseInt()}, this function recognizes the prefixes "0x"
* and "0" to signify hexadecimal and octal numbers, respectively. The
* result is coerced to a (signed) {@code int} when returned since Java has
* no unsigned integer type.
*/
static int parseUInt32(final String text) throws NumberFormatException {
return (int) parseInteger(text, false, false);
}
/**
* Parse a 64-bit signed integer from the text. Unlike the Java standard
* {@code Integer.parseInt()}, this function recognizes the prefixes "0x"
* and "0" to signify hexadecimal and octal numbers, respectively.
*/
static long parseInt64(final String text) throws NumberFormatException {
return parseInteger(text, true, true);
}
/**
* Parse a 64-bit unsigned integer from the text. Unlike the Java standard
* {@code Integer.parseInt()}, this function recognizes the prefixes "0x"
* and "0" to signify hexadecimal and octal numbers, respectively. The
* result is coerced to a (signed) {@code long} when returned since Java has
* no unsigned long type.
*/
static long parseUInt64(final String text) throws NumberFormatException {
return parseInteger(text, false, true);
}
private static long parseInteger(final String text,
final boolean isSigned,
final boolean isLong)
throws NumberFormatException {
int pos = 0;
boolean negative = false;
if (text.startsWith("-", pos)) {
if (!isSigned) {
throw new NumberFormatException("Number must be positive: " + text);
}
++pos;
negative = true;
}
int radix = 10;
if (text.startsWith("0x", pos)) {
pos += 2;
radix = 16;
} else if (text.startsWith("0", pos)) {
radix = 8;
}
final String numberText = text.substring(pos);
long result = 0;
if (numberText.length() < 16) {
// Can safely assume no overflow.
result = Long.parseLong(numberText, radix);
if (negative) {
result = -result;
}
// Check bounds.
// No need to check for 64-bit numbers since they'd have to be 16 chars
// or longer to overflow.
if (!isLong) {
if (isSigned) {
if (result > Integer.MAX_VALUE || result < Integer.MIN_VALUE) {
throw new NumberFormatException(
"Number out of range for 32-bit signed integer: " + text);
}
} else {
if (result >= (1L << 32) || result < 0) {
throw new NumberFormatException(
"Number out of range for 32-bit unsigned integer: " + text);
}
}
}
} else {
BigInteger bigValue = new BigInteger(numberText, radix);
if (negative) {
bigValue = bigValue.negate();
}
// Check bounds.
if (!isLong) {
if (isSigned) {
if (bigValue.bitLength() > 31) {
throw new NumberFormatException(
"Number out of range for 32-bit signed integer: " + text);
}
} else {
if (bigValue.bitLength() > 32) {
throw new NumberFormatException(
"Number out of range for 32-bit unsigned integer: " + text);
}
}
} else {
if (isSigned) {
if (bigValue.bitLength() > 63) {
throw new NumberFormatException(
"Number out of range for 64-bit signed integer: " + text);
}
} else {
if (bigValue.bitLength() > 64) {
throw new NumberFormatException(
"Number out of range for 64-bit unsigned integer: " + text);
}
}
}
result = bigValue.longValue();
}
return result;
}
}