| // Copyright 2014 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| package com.google.devtools.build.lib.shell; |
| |
| import java.nio.charset.StandardCharsets; |
| |
| /** |
| * Utilities for logging. |
| */ |
| class LogUtil { |
| |
| private LogUtil() {} |
| |
| private final static int TRUNCATE_STRINGS_AT = 150; |
| |
| /** |
| * Make a string out of a byte array, and truncate it to a reasonable length. |
| * Useful for preventing logs from becoming excessively large. |
| */ |
| static String toTruncatedString(final byte[] bytes) { |
| if(bytes == null || bytes.length == 0) { |
| return ""; |
| } |
| /* |
| * Yes, we'll use the platform encoding here, and this is one of the rare |
| * cases where it makes sense. You want the logs to be encoded so that |
| * your platform tools (vi, emacs, cat) can render them, don't you? |
| * In practice, this means ISO-8859-1 or UTF-8, I guess. |
| */ |
| try { |
| if (bytes.length > TRUNCATE_STRINGS_AT) { |
| return new String(bytes, 0, TRUNCATE_STRINGS_AT, StandardCharsets.UTF_8) |
| + "[... truncated. original size was " + bytes.length + " bytes.]"; |
| } |
| return new String(bytes); |
| } catch (Exception e) { |
| /* |
| * In case encoding a binary string doesn't work for some reason, we |
| * don't want to bring a logging server down - do we? So we're paranoid. |
| */ |
| return "IOUtil.toTruncatedString: " + e.getMessage(); |
| } |
| } |
| |
| } |