/*
* Copyright 2011 Google Inc. 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.errorprone;
import com.google.common.base.Function;
import com.google.common.collect.Lists;
import com.google.errorprone.fixes.AppliedFix;
import com.google.errorprone.fixes.Fix;
import com.google.errorprone.matchers.Description;
import com.sun.tools.javac.main.JavaCompiler;
import com.sun.tools.javac.tree.EndPosTable;
import com.sun.tools.javac.util.Context;
import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
import com.sun.tools.javac.util.Log;
import java.io.IOError;
import java.io.IOException;
import java.util.List;
import javax.tools.JavaFileObject;
/**
* Making our errors appear to the user and break their build.
* @author alexeagle@google.com (Alex Eagle)
*/
public class JavacErrorDescriptionListener implements DescriptionListener {
private final Log log;
private EndPosTable endPositions;
private final JavaFileObject sourceFile;
private final CharSequence sourceFileContent;
private final JavaCompiler compiler;
private final Function<Fix, AppliedFix> fixToAppliedFix = new Function<Fix, AppliedFix>() {
@Override
public AppliedFix apply(Fix fix) {
return AppliedFix.fromSource(sourceFileContent, endPositions).apply(fix);
}
};
// The suffix for properties in src/main/resources/com/google/errorprone/errors.properties
private static final String MESSAGE_BUNDLE_KEY = "error.prone";
public JavacErrorDescriptionListener(Log log, EndPosTable endPositions,
JavaFileObject sourceFile, Context context) {
this.log = log;
this.endPositions = endPositions;
this.sourceFile = sourceFile;
this.compiler = JavaCompiler.instance(context);
try {
this.sourceFileContent = sourceFile.getCharContent(true);
} catch (IOException e) {
throw new IOError(e);
}
}
@Override
public void onDescribed(Description description) {
// Swap the log's source and the current file's source; then be sure to swap them back later.
JavaFileObject originalSource = log.useSource(sourceFile);
// If endPositions were not computed (-Xjcov option was not passed), reparse the file
// and compute the end positions so we can generate suggested fixes.
if (EndPosTableUtil.isEmpty(endPositions)) {
boolean prevGenEndPos = compiler.genEndPos;
compiler.genEndPos = true;
// Reset the end positions for JDK8:
EndPosTableUtil.resetEndPosMap(compiler, sourceFile);
EndPosTable endPosMap = compiler.parse(sourceFile).endPositions;
compiler.genEndPos = prevGenEndPos;
endPositions = new WrappedTreeMap(log, endPosMap);
}
List<AppliedFix> appliedFixes = Lists.transform(description.fixes, fixToAppliedFix);
StringBuilder messageBuilder = new StringBuilder(description.getMessage());
boolean first = true;
for (AppliedFix appliedFix : appliedFixes) {
if (first) {
messageBuilder.append("\nDid you mean ");
} else {
messageBuilder.append(" or ");
}
if (appliedFix.isRemoveLine()) {
messageBuilder.append("to remove this line");
} else {
messageBuilder.append("'" + appliedFix.getNewCodeSnippet() + "'");
}
first = false;
}
if (!first) { // appended at least one suggested fix to the message
messageBuilder.append("?");
}
final String message = messageBuilder.toString();
switch (description.severity) {
case ERROR:
log.error((DiagnosticPosition) description.node, MESSAGE_BUNDLE_KEY, message);
break;
case WARNING:
log.warning((DiagnosticPosition) description.node, MESSAGE_BUNDLE_KEY, message);
break;
default:
break;
}
if (originalSource != null) {
log.useSource(originalSource);
}
}
}