alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Commons IO example source code file (FileCleaningTrackerTestCase.java)

This example Commons IO source code file (FileCleaningTrackerTestCase.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Commons IO tags/keywords

a, a, big, count, exception, exception, file, filecleaningtracker, io, nullpointerexception, object, object, randomaccessfile, string, string, util

The Commons IO FileCleaningTrackerTestCase.java source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.commons.io;

import java.io.File;
import java.io.RandomAccessFile;
import java.lang.ref.ReferenceQueue;
import java.util.ArrayList;
import java.util.List;

import org.apache.commons.io.testtools.FileBasedTestCase;

/**
 * This is used to test {@link FileCleaningTracker} for correctness.
 *
 * @author Noel Bergman
 * @author Martin Cooper
 *
 * @version $Id: FileCleaningTrackerTestCase.java 1006099 2010-10-09 01:55:02Z niallp $

 * @see FileCleaningTracker
 */
public class FileCleaningTrackerTestCase extends FileBasedTestCase {
    protected FileCleaningTracker newInstance() {
        return new FileCleaningTracker();
    }

    private File testFile;
    private FileCleaningTracker theInstance;

    public FileCleaningTrackerTestCase(String name) {
        super(name);
        testFile = new File(getTestDirectory(), "file-test.txt");
    }

    /** @see junit.framework.TestCase#setUp() */
    @Override
    protected void setUp() throws Exception {
        theInstance = newInstance();
        getTestDirectory().mkdirs();
    }

    /** @see junit.framework.TestCase#tearDown() */
    @Override
    protected void tearDown() throws Exception {
        FileUtils.deleteDirectory(getTestDirectory());
        
        // reset file cleaner class, so as not to break other tests

        /**
         * The following block of code can possibly be removed when the
         * deprecated {@link FileCleaner} is gone. The question is, whether
         * we want to support reuse of {@link FileCleaningTracker} instances,
         * which we should, IMO, not.
         */
        {
            theInstance.q = new ReferenceQueue<Object>();
            theInstance.trackers.clear();
            theInstance.deleteFailures.clear();
            theInstance.exitWhenFinished = false;
            theInstance.reaper = null;
        }
        
        theInstance = null;
    }

    //-----------------------------------------------------------------------
    public void testFileCleanerFile() throws Exception {
        String path = testFile.getPath();
        
        assertEquals(false, testFile.exists());
        RandomAccessFile r = new RandomAccessFile(testFile, "rw");
        assertEquals(true, testFile.exists());
        
        assertEquals(0, theInstance.getTrackCount());
        theInstance.track(path, r);
        assertEquals(1, theInstance.getTrackCount());
        
        r.close();
        testFile = null;
        r = null;

        waitUntilTrackCount();
        pauseForDeleteToComplete(new File(path));
        
        assertEquals(0, theInstance.getTrackCount());
        assertEquals(showFailures(), false, new File(path).exists());
    }

    public void testFileCleanerDirectory() throws Exception {
        createFile(testFile, 100);
        assertEquals(true, testFile.exists());
        assertEquals(true, getTestDirectory().exists());
        
        Object obj = new Object();
        assertEquals(0, theInstance.getTrackCount());
        theInstance.track(getTestDirectory(), obj);
        assertEquals(1, theInstance.getTrackCount());
        
        obj = null;

        waitUntilTrackCount();

        assertEquals(0, theInstance.getTrackCount());
        assertEquals(true, testFile.exists());  // not deleted, as dir not empty
        assertEquals(true, testFile.getParentFile().exists());  // not deleted, as dir not empty
    }

    public void testFileCleanerDirectory_NullStrategy() throws Exception {
        createFile(testFile, 100);
        assertEquals(true, testFile.exists());
        assertEquals(true, getTestDirectory().exists());
        
        Object obj = new Object();
        assertEquals(0, theInstance.getTrackCount());
        theInstance.track(getTestDirectory(), obj, (FileDeleteStrategy) null);
        assertEquals(1, theInstance.getTrackCount());
        
        obj = null;

        waitUntilTrackCount();
        
        assertEquals(0, theInstance.getTrackCount());
        assertEquals(true, testFile.exists());  // not deleted, as dir not empty
        assertEquals(true, testFile.getParentFile().exists());  // not deleted, as dir not empty
    }

    public void testFileCleanerDirectory_ForceStrategy() throws Exception {
        createFile(testFile, 100);
        assertEquals(true, testFile.exists());
        assertEquals(true, getTestDirectory().exists());
        
        Object obj = new Object();
        assertEquals(0, theInstance.getTrackCount());
        theInstance.track(getTestDirectory(), obj, FileDeleteStrategy.FORCE);
        assertEquals(1, theInstance.getTrackCount());
        
        obj = null;

        waitUntilTrackCount();
        pauseForDeleteToComplete(testFile.getParentFile());
        
        assertEquals(0, theInstance.getTrackCount());
        assertEquals(showFailures(), false, new File(testFile.getPath()).exists());
        assertEquals(showFailures(), false, testFile.getParentFile().exists());
    }

    public void testFileCleanerNull() throws Exception {
        try {
            theInstance.track((File) null, new Object());
            fail();
        } catch (NullPointerException ex) {
            // expected
        }
        try {
            theInstance.track((File) null, new Object(), FileDeleteStrategy.NORMAL);
            fail();
        } catch (NullPointerException ex) {
            // expected
        }
        try {
            theInstance.track((String) null, new Object());
            fail();
        } catch (NullPointerException ex) {
            // expected
        }
        try {
            theInstance.track((String) null, new Object(), FileDeleteStrategy.NORMAL);
            fail();
        } catch (NullPointerException ex) {
            // expected
        }
    }

    public void testFileCleanerExitWhenFinishedFirst() throws Exception {
        assertEquals(false, theInstance.exitWhenFinished);
        theInstance.exitWhenFinished();
        assertEquals(true, theInstance.exitWhenFinished);
        assertEquals(null, theInstance.reaper);
        
        waitUntilTrackCount();
        
        assertEquals(0, theInstance.getTrackCount());
        assertEquals(true, theInstance.exitWhenFinished);
        assertEquals(null, theInstance.reaper);
    }

    public void testFileCleanerExitWhenFinished_NoTrackAfter() throws Exception {
        assertEquals(false, theInstance.exitWhenFinished);
        theInstance.exitWhenFinished();
        assertEquals(true, theInstance.exitWhenFinished);
        assertEquals(null, theInstance.reaper);
        
        String path = testFile.getPath();
        Object marker = new Object();
        try {
            theInstance.track(path, marker);
            fail();
        } catch (IllegalStateException ex) {
            // expected
        }
        assertEquals(true, theInstance.exitWhenFinished);
        assertEquals(null, theInstance.reaper);
    }

    public void testFileCleanerExitWhenFinished1() throws Exception {
        String path = testFile.getPath();
        
        assertEquals("1-testFile exists", false, testFile.exists());
        RandomAccessFile r = new RandomAccessFile(testFile, "rw");
        assertEquals("2-testFile exists", true, testFile.exists());
        
        assertEquals("3-Track Count", 0, theInstance.getTrackCount());
        theInstance.track(path, r);
        assertEquals("4-Track Count", 1, theInstance.getTrackCount());
        assertEquals("5-exitWhenFinished", false, theInstance.exitWhenFinished);
        assertEquals("6-reaper.isAlive", true, theInstance.reaper.isAlive());
        
        assertEquals("7-exitWhenFinished", false, theInstance.exitWhenFinished);
        theInstance.exitWhenFinished();
        assertEquals("8-exitWhenFinished", true, theInstance.exitWhenFinished);
        assertEquals("9-reaper.isAlive", true, theInstance.reaper.isAlive());
        
        r.close();
        testFile = null;
        r = null;

        waitUntilTrackCount();
        pauseForDeleteToComplete(new File(path));
        
        assertEquals("10-Track Count", 0, theInstance.getTrackCount());
        assertEquals("11-testFile exists " + showFailures(), false, new File(path).exists());
        assertEquals("12-exitWhenFinished", true, theInstance.exitWhenFinished);
        assertEquals("13-reaper.isAlive", false, theInstance.reaper.isAlive());
    }

    public void testFileCleanerExitWhenFinished2() throws Exception {
        String path = testFile.getPath();
        
        assertEquals(false, testFile.exists());
        RandomAccessFile r = new RandomAccessFile(testFile, "rw");
        assertEquals(true, testFile.exists());
        
        assertEquals(0, theInstance.getTrackCount());
        theInstance.track(path, r);
        assertEquals(1, theInstance.getTrackCount());
        assertEquals(false, theInstance.exitWhenFinished);
        assertEquals(true, theInstance.reaper.isAlive());
        
        r.close();
        testFile = null;
        r = null;

        waitUntilTrackCount();
        pauseForDeleteToComplete(new File(path));
        
        assertEquals(0, theInstance.getTrackCount());
        assertEquals(showFailures(), false, new File(path).exists());
        assertEquals(false, theInstance.exitWhenFinished);
        assertEquals(true, theInstance.reaper.isAlive());
        
        assertEquals(false, theInstance.exitWhenFinished);
        theInstance.exitWhenFinished();
        for (int i = 0; i < 20 && theInstance.reaper.isAlive(); i++) {
            Thread.sleep(500L);  // allow reaper thread to die
        }
        assertEquals(true, theInstance.exitWhenFinished);
        assertEquals(false, theInstance.reaper.isAlive());
    }

    //-----------------------------------------------------------------------
    private void pauseForDeleteToComplete(File file) {
        int count = 0;
        while(file.exists() && count++ < 40) {
            try {
                Thread.sleep(500L);
            } catch (InterruptedException e) {
            }
            file = new File(file.getPath());
        }
    }
    private String showFailures() throws Exception {
        if (theInstance.deleteFailures.size() == 1) {
            return "[Delete Failed: " + theInstance.deleteFailures.get(0) + "]";
        } else {
            return "[Delete Failures: " + theInstance.deleteFailures.size() + "]";
        }
    }

    private void waitUntilTrackCount() throws Exception {
        System.gc(); 
        Thread.sleep(500);
        int count = 0;
        while(theInstance.getTrackCount() != 0 && count++ < 5) {
            List<String> list = new ArrayList();
            try {
                long i = 0;
                while (theInstance.getTrackCount() != 0) {
                    list.add("A Big String A Big String A Big String A Big String A Big String A Big String A Big String A Big String A Big String A Big String " + (i++));
                }
            } catch (Throwable ignored) {
            }
            list = null;
            System.gc(); 
            Thread.sleep(1000);
        }
        if (theInstance.getTrackCount() != 0) {
            throw new IllegalStateException("Your JVM is not releasing References, try running the testcase with less memory (-Xmx)");
        }
        
    }
}

Other Commons IO examples (source code examples)

Here is a short list of links related to this Commons IO FileCleaningTrackerTestCase.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.