Java tutorial
// 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.analysis.actions; import com.google.common.annotations.VisibleForTesting; import com.google.common.collect.ImmutableList; import com.google.common.collect.Iterables; import com.google.devtools.build.lib.actions.ActionExecutionContext; import com.google.devtools.build.lib.actions.ActionOwner; import com.google.devtools.build.lib.actions.Artifact; import com.google.devtools.build.lib.actions.Artifact.ArtifactExpander; import com.google.devtools.build.lib.actions.ParameterFile.ParameterFileType; import com.google.devtools.build.lib.analysis.actions.AbstractFileWriteAction.DeterministicWriter; import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable; import com.google.devtools.build.lib.util.Fingerprint; import com.google.devtools.build.lib.util.Preconditions; import com.google.devtools.build.lib.util.ShellEscaper; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.nio.charset.Charset; /** * Action to write a parameter file for a {@link CommandLine}. */ @Immutable // if commandLine and charset are immutable public final class ParameterFileWriteAction extends AbstractFileWriteAction { private static final String GUID = "45f678d8-e395-401e-8446-e795ccc6361f"; private final CommandLine commandLine; private final ParameterFileType type; private final Charset charset; private final boolean hasInputArtifactToExpand; /** * Creates a new instance. * * @param owner the action owner * @param output the Artifact that will be created by executing this Action * @param commandLine the contents to be written to the file * @param type the type of the file * @param charset the charset of the file */ public ParameterFileWriteAction(ActionOwner owner, Artifact output, CommandLine commandLine, ParameterFileType type, Charset charset) { this(owner, ImmutableList.<Artifact>of(), output, commandLine, type, charset); } /** * Creates a new instance. * * @param owner the action owner * @param inputs the list of TreeArtifacts that must be resolved and expanded before evaluating * the contents of {@link commandLine}. * @param output the Artifact that will be created by executing this Action * @param commandLine the contents to be written to the file * @param type the type of the file * @param charset the charset of the file */ public ParameterFileWriteAction(ActionOwner owner, Iterable<Artifact> inputs, Artifact output, CommandLine commandLine, ParameterFileType type, Charset charset) { super(owner, ImmutableList.copyOf(inputs), output, false); this.commandLine = commandLine; this.type = type; this.charset = charset; this.hasInputArtifactToExpand = !Iterables.isEmpty(inputs); } /** * Returns the list of options written to the parameter file. Don't use this * method outside tests - the list is often huge, resulting in significant * garbage collection overhead. */ @VisibleForTesting public Iterable<String> getContents() { Preconditions.checkState(!hasInputArtifactToExpand, "This action contains a CommandLine with TreeArtifacts: %s, which must be expanded using " + "ArtifactExpander first before we can evaluate the CommandLine.", getInputs()); return commandLine.arguments(); } @VisibleForTesting public Iterable<String> getContents(ArtifactExpander artifactExpander) { return commandLine.arguments(artifactExpander); } @Override public DeterministicWriter newDeterministicWriter(ActionExecutionContext ctx) { return new ParamFileWriter(Preconditions.checkNotNull(ctx.getArtifactExpander())); } private class ParamFileWriter implements DeterministicWriter { private final ArtifactExpander artifactExpander; ParamFileWriter(ArtifactExpander artifactExpander) { this.artifactExpander = artifactExpander; } @Override public void writeOutputFile(OutputStream out) throws IOException { Iterable<String> arguments = commandLine.arguments(artifactExpander); switch (type) { case SHELL_QUOTED: writeContentQuoted(out, arguments); break; case UNQUOTED: writeContentUnquoted(out, arguments); break; default: throw new AssertionError(); } } /** * Writes the arguments from the list into the parameter file. */ private void writeContentUnquoted(OutputStream outputStream, Iterable<String> arguments) throws IOException { OutputStreamWriter out = new OutputStreamWriter(outputStream, charset); for (String line : arguments) { out.write(line); out.write('\n'); } out.flush(); } /** * Writes the arguments from the list into the parameter file with shell * quoting (if required). */ private void writeContentQuoted(OutputStream outputStream, Iterable<String> arguments) throws IOException { OutputStreamWriter out = new OutputStreamWriter(outputStream, charset); for (String line : ShellEscaper.escapeAll(arguments)) { out.write(line); out.write('\n'); } out.flush(); } } @Override protected String computeKey() { Fingerprint f = new Fingerprint(); f.addString(GUID); f.addString(String.valueOf(makeExecutable)); f.addStrings(commandLine.arguments()); return f.hexDigestAndReset(); } }