com.google.gwt.dev.util.OutputFileSet Maven / Gradle / Ivy
/*
* Copyright 2009 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.dev.util;
import java.io.IOException;
import java.io.OutputStream;
import java.util.HashSet;
import java.util.Set;
/**
* An abstract set of files that a linker links into.
*/
public abstract class OutputFileSet {
/**
* Indicates that the file should be overwritten.
*/
public static final int TIMESTAMP_UNAVAILABLE = -1;
private final String pathDescription;
private final Set pathsSeen = new HashSet();
protected OutputFileSet(String pathDescription) {
this.pathDescription = pathDescription;
}
public boolean alreadyContains(String path) {
return pathsSeen.contains(path);
}
/**
* No more output will be sent to this OutputFileSet. It is safe to call
* {@link #close()} on an already-closed instance.
*
* @throws IOException
*/
public abstract void close() throws IOException;
/**
* Return a description of this output file set's path. The precise meaning is
* unspecified, except that it should be informative when used in log
* messages.
*/
public String getPathDescription() {
return pathDescription;
}
/**
* Opens a file for write. If writing to a zip file and the file already exists,
* this has no effect. Otherwise, overwrites any existing file.
* @return the output stream to write to, possibly a NullOutputStream
*/
public final OutputStream openForWrite(String path) throws IOException {
return openForWrite(path, TIMESTAMP_UNAVAILABLE);
}
/**
* Opens a file for write. If writing to a zip file and the file already
* exists, there will be no effect. If writing to a directory, the file
* exists, and the given timestamp is older or equal to the file's
* current timestamp, there will be no effect.
* @param timeStampMillis last modified time in milliseconds, or
* TIMESTAMP_UNAVAILABLE to force an overwrite.
* @return the output stream to write to, possibly a NullOutputStream
*/
public OutputStream openForWrite(String path, long timeStampMillis)
throws IOException {
pathsSeen.add(path);
return createNewOutputStream(path, timeStampMillis);
}
protected abstract OutputStream createNewOutputStream(String path,
long lastModifiedTime) throws IOException;
}