Implement an abstraction layer over java.lang.Process so that the Windows implementation can eventually be plugged in.
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MOS_MIGRATED_REVID=126404913
diff --git a/src/main/java/com/google/devtools/build/lib/shell/Subprocess.java b/src/main/java/com/google/devtools/build/lib/shell/Subprocess.java
new file mode 100644
index 0000000..99e5577
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/shell/Subprocess.java
@@ -0,0 +1,68 @@
+// Copyright 2016 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.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+ * A process started by Bazel.
+ */
+public interface Subprocess {
+
+ /**
+ * Something that can create subprocesses.
+ */
+ interface Factory {
+
+ /**
+ * Create a subprocess according to the specified parameters.
+ */
+ Subprocess create(SubprocessBuilder params) throws IOException;
+ }
+
+ /**
+ * Kill the process.
+ */
+ boolean destroy();
+
+ /**
+ * Returns the exit value of the process.
+ *
+ * <p>Throws {@code IllegalThreadStateException} if the process has not terminated yet.
+ */
+ int exitValue();
+
+ /**
+ * Waits for the process to finish.
+ */
+ int waitFor() throws InterruptedException;
+
+ /**
+ * Returns a stream into which data can be written that the process will get on its stdin.
+ */
+ OutputStream getOutputStream();
+
+ /**
+ * Returns a stream from which the stdout of the process can be read.
+ */
+ InputStream getInputStream();
+
+ /**
+ * Returns a stream from which the stderr of the process can be read.
+ */
+ InputStream getErrorStream();
+}
