com.google.gwt.codegen.server.AbortablePrintWriter Maven / Gradle / Ivy
/*
* Copyright 2011 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.gwt.codegen.server;
import java.io.PrintWriter;
/**
* Wrapper for a {@link PrintWriter} that adds the ability to abort creation
* and an onClose hook
*
* Experimental API - subject to change.
*/
public class AbortablePrintWriter extends PrintWriter {
private boolean isClosed = false;
/**
* Wrap a {@link PrintWriter} instance.
*
* @param pw
* @throws RuntimeException if there are reflection errors accessing the out
* field in pw
*/
public AbortablePrintWriter(PrintWriter pw) {
super(pw);
}
/**
* Abort creation of this output.
*/
public void abort() {
if (!isClosed) {
flush();
super.close();
isClosed = true;
onClose(true);
}
}
@Override
public void close() {
if (!isClosed) {
flush();
super.close();
isClosed = true;
onClose(false);
}
}
/**
* Called exactly once when this {@link PrintWriter} is closed or aborted.
*
* @param aborted
*/
protected void onClose(boolean aborted) {
// Do nothing by default.
}
}