/*
* Copyright (C) 2013 Google, Inc.
*
* 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.testing.compile;
import com.google.common.base.MoreObjects;
import com.google.common.base.Optional;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import com.google.common.collect.ImmutableList;
import com.google.common.io.ByteSource;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.StringWriter;
import java.io.Writer;
import java.net.URI;
import java.nio.charset.Charset;
import java.util.Map.Entry;
import javax.tools.FileObject;
import javax.tools.JavaFileObject;
import javax.tools.JavaFileObject.Kind;
import javax.tools.SimpleJavaFileObject;
import javax.tools.StandardJavaFileManager;
import javax.tools.StandardLocation;
/**
* A file manager implementation that stores all output in memory.
*
* @author Gregory Kick
*/
// TODO(gak): under java 1.7 this could all be done with a PathFileManager
final class InMemoryJavaFileManager extends ForwardingStandardJavaFileManager {
private final LoadingCache<URI, JavaFileObject> inMemoryFileObjects =
CacheBuilder.newBuilder().build(new CacheLoader<URI, JavaFileObject>() {
@Override
public JavaFileObject load(URI key) {
return new InMemoryJavaFileObject(key);
}
});
InMemoryJavaFileManager(StandardJavaFileManager fileManager) {
super(fileManager);
}
private static URI uriForFileObject(Location location, String packageName, String relativeName) {
StringBuilder uri = new StringBuilder("mem:///").append(location.getName()).append('/');
if (!packageName.isEmpty()) {
uri.append(packageName.replace('.', '/')).append('/');
}
uri.append(relativeName);
return URI.create(uri.toString());
}
private static URI uriForJavaFileObject(Location location, String className, Kind kind) {
return URI.create(
"mem:///" + location.getName() + '/' + className.replace('.', '/') + kind.extension);
}
@Override
public boolean isSameFile(FileObject a, FileObject b) {
/* This check is less strict than what is typically done by the normal compiler file managers
* (e.g. JavacFileManager), but is actually the moral equivalent of what most of the
* implementations do anyway. We use this check rather than just delegating to the compiler's
* file manager because file objects for tests generally cause IllegalArgumentExceptions. */
return a.toUri().equals(b.toUri());
}
@Override
public FileObject getFileForInput(Location location, String packageName,
String relativeName) throws IOException {
if (location.isOutputLocation()) {
return inMemoryFileObjects.getIfPresent(
uriForFileObject(location, packageName, relativeName));
} else {
return super.getFileForInput(location, packageName, relativeName);
}
}
@Override
public JavaFileObject getJavaFileForInput(Location location, String className, Kind kind)
throws IOException {
if (location.isOutputLocation()) {
return inMemoryFileObjects.getIfPresent(uriForJavaFileObject(location, className, kind));
} else {
return super.getJavaFileForInput(location, className, kind);
}
}
@Override
public FileObject getFileForOutput(Location location, String packageName,
String relativeName, FileObject sibling) throws IOException {
URI uri = uriForFileObject(location, packageName, relativeName);
return inMemoryFileObjects.getUnchecked(uri);
}
@Override
public JavaFileObject getJavaFileForOutput(Location location, String className, final Kind kind,
FileObject sibling) throws IOException {
URI uri = uriForJavaFileObject(location, className, kind);
return inMemoryFileObjects.getUnchecked(uri);
}
ImmutableList<JavaFileObject> getGeneratedSources() {
ImmutableList.Builder<JavaFileObject> result = ImmutableList.builder();
for (Entry<URI, JavaFileObject> entry : inMemoryFileObjects.asMap().entrySet()) {
if (entry.getKey().getPath().startsWith("/" + StandardLocation.SOURCE_OUTPUT.name())
&& (entry.getValue().getKind() == Kind.SOURCE)) {
result.add(entry.getValue());
}
}
return result.build();
}
ImmutableList<JavaFileObject> getOutputFiles() {
return ImmutableList.copyOf(inMemoryFileObjects.asMap().values());
}
private static final class InMemoryJavaFileObject extends SimpleJavaFileObject
implements JavaFileObject {
private long lastModified = 0L;
private Optional<ByteSource> data = Optional.absent();
InMemoryJavaFileObject(URI uri) {
super(uri, JavaFileObjects.deduceKind(uri));
}
@Override
public InputStream openInputStream() throws IOException {
if (data.isPresent()) {
return data.get().openStream();
} else {
throw new FileNotFoundException();
}
}
@Override
public OutputStream openOutputStream() throws IOException {
return new ByteArrayOutputStream() {
@Override
public void close() throws IOException {
super.close();
data = Optional.of(ByteSource.wrap(toByteArray()));
lastModified = System.currentTimeMillis();
}
};
}
@Override
public Reader openReader(boolean ignoreEncodingErrors) throws IOException {
if (data.isPresent()) {
return data.get().asCharSource(Charset.defaultCharset()).openStream();
} else {
throw new FileNotFoundException();
}
}
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors)
throws IOException {
if (data.isPresent()) {
return data.get().asCharSource(Charset.defaultCharset()).read();
} else {
throw new FileNotFoundException();
}
}
@Override
public Writer openWriter() throws IOException {
return new StringWriter() {
@Override
public void close() throws IOException {
super.close();
data =
Optional.of(ByteSource.wrap(toString().getBytes(Charset.defaultCharset())));
lastModified = System.currentTimeMillis();
}
};
}
@Override
public long getLastModified() {
return lastModified;
}
@Override
public boolean delete() {
this.data = Optional.absent();
this.lastModified = 0L;
return true;
}
@Override
public String toString() {
return MoreObjects.toStringHelper(this)
.add("uri", toUri())
.add("kind", kind)
.toString();
}
}
}
