de.schlichtherle.truezip.sample.file.app.Application Maven / Gradle / Ivy
/*
* Copyright (C) 2007-2011 Schlichtherle IT Services
*
* 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 de.schlichtherle.truezip.sample.file.app;
import de.schlichtherle.truezip.crypto.raes.param.swing.HurlingWindowFeedback;
import de.schlichtherle.truezip.file.TFile;
import de.schlichtherle.truezip.fs.FsStatistics;
import de.schlichtherle.truezip.crypto.raes.param.swing.InvalidKeyFeedback;
import de.schlichtherle.truezip.file.TApplication;
import de.schlichtherle.truezip.fs.FsSyncException;
import de.schlichtherle.truezip.fs.spi.FsManagerService;
import edu.umd.cs.findbugs.annotations.DefaultAnnotation;
import edu.umd.cs.findbugs.annotations.NonNull;
import java.io.OutputStream;
import java.io.PrintStream;
import java.text.MessageFormat;
/**
* Abstract base class for command line utilities.
*
* @author Christian Schlichtherle
* @version $Id$
*/
@DefaultAnnotation(NonNull.class)
abstract class Application extends TApplication {
/** The print stream for standard output. */
protected final PrintStream out;
/** The print stream for error output. */
protected final PrintStream err;
/** A progress monitor for {@link TFile#umount()}. */
protected final ProgressMonitor monitor;
/**
* Equivalent to
* {@link #Application(OutputStream, OutputStream, boolean)
* Application(System.out, System.err, true)}.
*/
protected Application() {
this(System.out, System.err, true);
}
/**
* Constructs a new command line utility instance.
*
* Note that this constructor has side effects:
*
* - If Swing based prompting is used, the Hurling Window Feedback is
* set for feedback on wrong key entry unless the respective system
* properties have been explicitly set.
*
- Similarly, the {@link SampleManagerService} class is set for
* obtaining statistics when synchronizing any uncommitted changes to
* the contents of archive files.
*
*
* @param out the standard output stream.
* @param err the error output stream.
* @param autoFlush if the output streams are not {@link PrintStream}s,
* then they are wrapped in a new {@code PrintStream} with
* this as the additional constructor parameter.
*/
protected Application(
final OutputStream out,
final OutputStream err,
final boolean autoFlush) {
this.out = out instanceof PrintStream
? (PrintStream) out
: new PrintStream(out, autoFlush);
this.err = err instanceof PrintStream
? (PrintStream) err
: new PrintStream(err, autoFlush);
this.monitor = new ProgressMonitor(this.err);
String spec = FsManagerService.class.getName();
String impl = SampleManagerService.class.getName();
System.setProperty(spec, System.getProperty(spec, impl));
}
/**
* Runs the setup phase.
*
* This method is {@link #run run} only once at the start of the life
* cycle.
* Its task is to configure the default behavior of the TrueZIP File* API
* in order to answer the following questions:
*
* - What are the file suffixes which shall be recognized as archive
* files and hence as virtual directories?
*
- Shall missing archive files and directory entries get automatically
* created whenever required?
*
*
* The implementation in the class {@link Application} configures
* the type of the feedback when prompting the user for keys for RAES
* encrypted ZIP alias ZIP.RAES alias TZP files by the Swing based
* prompting key manager.
* If this JVM is running in headless mode, then this configuration is
* ignored and the user is prompted by the console I/O based prompting
* key manager.
*/
@Override
protected void setup() {
String spec = InvalidKeyFeedback.class.getName();
String impl = HurlingWindowFeedback.class.getName();
System.setProperty(spec, System.getProperty(spec, impl));
}
/**
* Runs the work phase by calling {@link #runChecked}.
* Prints a user readable error message to the error output stream
* which was provided to the constructor if an {@link Exception occurs}.
*
* This method is {@link #run run} at least once and repeatedly called
* until {@link #runChecked} returns a non-negative integer for use as the
* {@link System#exit(int) exist status} of the VM.
* After this method, the {@link #sync} method is called in a
* finally-block.
*
* @param args an array of arguments for this command line utility.
* @return A negative integer in order to continue calling this method
* in a loop.
* Otherwise, the return value is used as the
* {@link System#exit(int) exit status} of the VM.
* @throws RuntimeException at the discretion of {@link #runChecked}.
*/
@Override
protected final int work(final String[] args) {
try {
return runChecked(args);
} catch (RuntimeException ex) {
throw ex;
} catch (Exception ex) {
err.println(ex.getLocalizedMessage());
return 1;
}
}
/**
* Runs this command line utility.
* Throws an exception if an error occurs.
*
* Avoid repeating this method and updating the same archive file upon
* each call!
* This would degrade the overall performance from O(n) to O(m*n),
* where m is the number of new or modified entries and n is the number
* of all entries in the archive file!
*
* @param args an array of arguments for this command line utility.
* @return A negative integer in order to continue calling this method
* in a loop.
* Otherwise, the return value is used as the
* {@link System#exit(int) exit status} of the VM.
* @throws Exception on any exception.
*/
protected abstract int runChecked(String[] args) throws Exception;
@Override
protected void sync() throws FsSyncException {
try {
TFile.umount();
} finally {
monitor.shutdown();
}
}
/** Indicates illegal application parameters. */
protected static class IllegalUsageException extends Exception {
private static final long serialVersionUID = 1985623981423542464L;
protected IllegalUsageException(String msg) {
super(msg);
}
} // class IllegalUsageException
/**
* Monitors progress when committing unsynchronized changes to the
* contents of archive files.
*/
protected static final class ProgressMonitor extends Thread {
private final PrintStream err;
private final Long[] args = new Long[2];
private final FsStatistics stats;
private ProgressMonitor(final PrintStream err) {
setDaemon(true);
setPriority(Thread.MAX_PRIORITY);
this.err = err;
this.stats = SampleManagerService.manager.getStatistics();
}
@Override
public void start() {
if (err == System.err || err == System.out)
super.start();
}
@Override
public void run() {
boolean run = false;
for (long sleep = 2000; ; sleep = 200, run = true) {
try {
Thread.sleep(sleep);
} catch (InterruptedException shutdown) {
break;
}
showProgress();
}
if (run) {
showProgress();
err.println();
}
}
/**
* Prints statistics about the amount of data read and written by
* {@link TFile#umount()} on standard output.
*/
private void showProgress() {
// Round up to kilobytes.
args[0] = (stats.getTopLevelRead() + 1023) / 1024;
args[1] = (stats.getTopLevelWritten() + 1023) / 1024;
err.print(MessageFormat.format(
"Top level archive I/O: {0}/{1} KB \r", (Object[]) args));
err.flush();
}
@SuppressWarnings("CallToThreadDumpStack")
private void shutdown() {
interrupt();
try {
join();
} catch (InterruptedException interrupted) {
interrupted.printStackTrace();
}
}
} // class ProgressMonitor
}