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Android example source code file (ZipFileTest.java)

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

Java - Android tags/keywords

android, enumeration, exception, fileoutputstream, inputstream, io, ioexception, mediumtest, sample_size, test, testcase, this, util, zip, zipentry, zipfile, zipfiletest, zipoutputstream

The ZipFileTest.java Android example source code

/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * 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 android.core;

import junit.framework.TestCase;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import java.util.zip.ZipOutputStream;
import android.test.suitebuilder.annotation.MediumTest;


/**
 * Basic tests for ZipFile.
 */
public class ZipFileTest extends TestCase {
    private static final int SAMPLE_SIZE = 128 * 1024;

    @MediumTest
    public void testZipFile() throws Exception {

        File file = File.createTempFile("ZipFileTest", ".zip");
        try {
            // create a test file; assume it's not going to collide w/anything
            FileOutputStream outStream = new FileOutputStream(file);
            createCompressedZip(outStream);
//            System.out.println("CREATED " + file);

            scanZip(file.getPath());
            read2(file.getPath());
        } finally {
            file.delete();
        }
    }

    /*
     * stepStep == 0 --> >99% compression
     * stepStep == 1 --> ~30% compression
     * stepStep == 2 --> no compression
     */
    static byte[] makeSampleFile(int stepStep) throws IOException {
        byte[] sample = new byte[SAMPLE_SIZE];
        byte val, step;
        int i, j, offset;

        val = 0;
        step = 1;
        offset = 0;
        for (i = 0; i < SAMPLE_SIZE / 256; i++) {
            for (j = 0; j < 256; j++) {
                sample[offset++] = val;
                val += step;
            }

            step += stepStep;
        }

        return sample;
    }

    static void createCompressedZip(OutputStream bytesOut) throws IOException {
        ZipOutputStream out = new ZipOutputStream(bytesOut);
        try {
            int i;

            for (i = 0; i < 3; i++) {
                byte[] input = makeSampleFile(i);
                ZipEntry newEntry = new ZipEntry("file-" + i);

                if (i != 1) {
                    newEntry.setComment("this is file " + i);
                }
                out.putNextEntry(newEntry);
                out.write(input, 0, input.length);
                out.closeEntry();
            }

            out.setComment("This is a lovely compressed archive!");
        } finally {
            out.close();
        }
    }

    static void scanZip(String fileName) throws IOException {
        ZipFile zipFile = new ZipFile(fileName);
        Enumeration fileList;
        int idx = 0;

//        System.out.println("Contents of " + zipFile + ":");
        for (fileList = zipFile.entries(); fileList.hasMoreElements();) {
            ZipEntry entry = (ZipEntry) fileList.nextElement();
//            System.out.println("  " + entry.getName());
            assertEquals(entry.getName(), "file-" + idx);
            idx++;
        }

        zipFile.close();
    }

    /*
     * Read compressed data from two different entries at the same time,
     * to verify that the streams aren't getting confused.  If we do
     * something wrong, the inflater will choke and throw a ZipException.
     *
     * This doesn't test synchronization in multi-threaded use.
     */
    static void read2(String fileName) throws IOException {
        ZipFile zipFile;
        ZipEntry entry1, entry2;
        byte buf[] = new byte[16384];
        InputStream stream1, stream2;
        int len, totalLen1, totalLen2;

        /* use file-1 and file-2 because the compressed data is large */
        zipFile = new ZipFile(fileName);
        entry1 = zipFile.getEntry("file-1");
        entry2 = zipFile.getEntry("file-2");

        /* make sure we got the right thing */
        assertEquals("file-1", entry1.getName());
        assertEquals("file-2", entry2.getName());

        /* create streams */
        stream1 = zipFile.getInputStream(entry1);
        stream2 = zipFile.getInputStream(entry2);

        /*
         * Read a piece of file #1.
         */
        totalLen1 = stream1.read(buf);
        assertTrue("initial read failed on #1", totalLen1 >= 0);

        /*
         * Read a piece of file #2.
         */
        totalLen2 = stream2.read(buf);
        assertTrue("initial read failed on #2", totalLen2 >= 0);

        /*
         * Read the rest of file #1, and close the stream.
         *
         * If our streams are crossed up, we'll fail here.
         */
        while ((len = stream1.read(buf)) > 0) {
            totalLen1 += len;
        }
        assertEquals(SAMPLE_SIZE, totalLen1);
        stream1.close();

        /*
         * Read the rest of file #2, and close the stream.
         */
        while ((len = stream2.read(buf)) > 0) {
            totalLen2 += len;
        }
        assertEquals(SAMPLE_SIZE, totalLen2);
        stream2.close();

        /*
         * Open a new one.
         */
        stream1 = zipFile.getInputStream(zipFile.getEntry("file-0"));

        /*
         * Close the ZipFile. According to the RI, none if its InputStreams can
         * be read after this point.
         */
        zipFile.close();
        
        Exception error = null;
        try {
            stream1.read(buf);
        } catch (Exception ex) {
            error = ex;
        }
        
        assertNotNull("ZipFile shouldn't allow reading of closed files.", error);
    }
}

Other Android examples (source code examples)

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