testdocumentinputstream.java

介绍java核心技术的pio编程方法以及基本概念

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   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,
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   See the License for the specific language governing permissions and
   limitations under the License.
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package org.apache.poi.poifs.filesystem;

import java.io.*;

import java.util.*;

import junit.framework.*;

import org.apache.poi.poifs.property.DirectoryProperty;
import org.apache.poi.poifs.property.DocumentProperty;
import org.apache.poi.poifs.storage.RawDataBlock;

/**
 * Class to test DocumentInputStream functionality
 *
 * @author Marc Johnson
 */

public class TestDocumentInputStream
    extends TestCase
{

    /**
     * Constructor TestDocumentInputStream
     *
     * @param name
     *
     * @exception IOException
     */

    public TestDocumentInputStream(String name)
        throws IOException
    {
        super(name);
        int blocks = (_workbook_size + 511) / 512;

        _workbook_data = new byte[ 512 * blocks ];
        Arrays.fill(_workbook_data, ( byte ) -1);
        for (int j = 0; j < _workbook_size; j++)
        {
            _workbook_data[ j ] = ( byte ) (j * j);
        }
        RawDataBlock[]       rawBlocks = new RawDataBlock[ blocks ];
        ByteArrayInputStream stream    =
            new ByteArrayInputStream(_workbook_data);

        for (int j = 0; j < blocks; j++)
        {
            rawBlocks[ j ] = new RawDataBlock(stream);
        }
        POIFSDocument document = new POIFSDocument("Workbook", rawBlocks,
                                                   _workbook_size);

        _workbook = new DocumentNode(
            document.getDocumentProperty(),
            new DirectoryNode(
                new DirectoryProperty("Root Entry"), null, null));
    }

    private DocumentNode     _workbook;
    private byte[]           _workbook_data;
    private static final int _workbook_size = 5000;

    // non-even division of _workbook_size, also non-even division of
    // any block size
    private static final int _buffer_size   = 6;

    /**
     * test constructor
     *
     * @exception IOException
     */

    public void testConstructor()
        throws IOException
    {
        DocumentInputStream stream = new DocumentInputStream(_workbook);

        assertEquals(_workbook_size, stream.available());
    }

    /**
     * test available() behavior
     *
     * @exception IOException
     */

    public void testAvailable()
        throws IOException
    {
        DocumentInputStream stream = new DocumentInputStream(_workbook);

        assertEquals(_workbook_size, stream.available());
        stream.close();
        try
        {
            stream.available();
            fail("Should have caught IOException");
        }
        catch (IOException ignored)
        {

            // as expected
        }
    }

    /**
     * test mark/reset/markSupported.
     *
     * @exception IOException
     */

    public void testMarkFunctions()
        throws IOException
    {
        DocumentInputStream stream = new DocumentInputStream(_workbook);
        byte[]              buffer = new byte[ _workbook_size / 5 ];

        stream.read(buffer);
        for (int j = 0; j < buffer.length; j++)
        {
            assertEquals("checking byte " + j, _workbook_data[ j ],
                         buffer[ j ]);
        }
        assertEquals(_workbook_size - buffer.length, stream.available());
        stream.reset();
        assertEquals(_workbook_size, stream.available());
        stream.read(buffer);
        stream.mark(12);
        stream.read(buffer);
        assertEquals(_workbook_size - (2 * buffer.length),
                     stream.available());
        for (int j = buffer.length; j < (2 * buffer.length); j++)
        {
            assertEquals("checking byte " + j, _workbook_data[ j ],
                         buffer[ j - buffer.length ]);
        }
        stream.reset();
        assertEquals(_workbook_size - buffer.length, stream.available());
        stream.read(buffer);
        assertEquals(_workbook_size - (2 * buffer.length),
                     stream.available());
        for (int j = buffer.length; j < (2 * buffer.length); j++)
        {
            assertEquals("checking byte " + j, _workbook_data[ j ],
                         buffer[ j - buffer.length ]);
        }
        assertTrue(stream.markSupported());
    }

    /**
     * test simple read method
     *
     * @exception IOException
     */

    public void testReadSingleByte()
        throws IOException
    {
        DocumentInputStream stream    = new DocumentInputStream(_workbook);
        int                 remaining = _workbook_size;

        for (int j = 0; j < _workbook_size; j++)
        {
	    int b = stream.read();
	    assertTrue("checking sign of " + j, b >= 0);
            assertEquals("validating byte " + j, _workbook_data[ j ],
                         ( byte ) b);
            remaining--;
            assertEquals("checking remaining after reading byte " + j,
                         remaining, stream.available());
        }
        assertEquals(-1, stream.read());
        stream.close();
        try
        {
            stream.read();
            fail("Should have caught IOException");
        }
        catch (IOException ignored)
        {

            // as expected
        }
    }

    /**
     * Test buffered read
     *
     * @exception IOException
     */

    public void testBufferRead()
        throws IOException
    {
        DocumentInputStream stream = new DocumentInputStream(_workbook);

        try
        {
            stream.read(null);
            fail("Should have caught NullPointerException");
        }
        catch (NullPointerException ignored)
        {

            // as expected
        }

        // test reading zero length buffer
        assertEquals(0, stream.read(new byte[ 0 ]));
        assertEquals(_workbook_size, stream.available());
        byte[] buffer = new byte[ _buffer_size ];
        int    offset = 0;

        while (stream.available() >= buffer.length)
        {
            assertEquals(_buffer_size, stream.read(buffer));
            for (int j = 0; j < buffer.length; j++)
            {
                assertEquals("in main loop, byte " + offset,
                             _workbook_data[ offset ], buffer[ j ]);
                offset++;
            }
            assertEquals("offset " + offset, _workbook_size - offset,
                         stream.available());
        }
        assertEquals(_workbook_size % _buffer_size, stream.available());
        Arrays.fill(buffer, ( byte ) 0);
        int count = stream.read(buffer);

        assertEquals(_workbook_size % _buffer_size, count);
        for (int j = 0; j < count; j++)
        {
            assertEquals("past main loop, byte " + offset,
                         _workbook_data[ offset ], buffer[ j ]);
            offset++;
        }
        assertEquals(_workbook_size, offset);
        for (int j = count; j < buffer.length; j++)
        {
            assertEquals("checking remainder, byte " + j, 0, buffer[ j ]);
        }
        assertEquals(-1, stream.read(buffer));
        stream.close();
        try
        {
            stream.read(buffer);
            fail("Should have caught IOException");
        }
        catch (IOException ignored)
        {

            // as expected
        }
    }

    /**
     * Test complex buffered read
     *
     * @exception IOException
     */

    public void testComplexBufferRead()
        throws IOException
    {
        DocumentInputStream stream = new DocumentInputStream(_workbook);

        try
        {
            stream.read(null, 0, 1);
            fail("Should have caught NullPointerException");
        }
        catch (NullPointerException ignored)
        {

            // as expected
        }

        // test illegal offsets and lengths
        try
        {
            stream.read(new byte[ 5 ], -4, 0);
            fail("Should have caught IndexOutOfBoundsException");
        }
        catch (IndexOutOfBoundsException ignored)
        {

            // as expected
        }
        try
        {
            stream.read(new byte[ 5 ], 0, -4);
            fail("Should have caught IndexOutOfBoundsException");
        }
        catch (IndexOutOfBoundsException ignored)
        {

            // as expected
        }
        try
        {
            stream.read(new byte[ 5 ], 0, 6);
            fail("Should have caught IndexOutOfBoundsException");
        }
        catch (IndexOutOfBoundsException ignored)
        {

            // as expected
        }

        // test reading zero
        assertEquals(0, stream.read(new byte[ 5 ], 0, 0));
        assertEquals(_workbook_size, stream.available());
        byte[] buffer = new byte[ _workbook_size ];
        int    offset = 0;

        while (stream.available() >= _buffer_size)
        {
            Arrays.fill(buffer, ( byte ) 0);
            assertEquals(_buffer_size,
                         stream.read(buffer, offset, _buffer_size));
            for (int j = 0; j < offset; j++)
            {
                assertEquals("checking byte " + j, 0, buffer[ j ]);
            }
            for (int j = offset; j < (offset + _buffer_size); j++)
            {
                assertEquals("checking byte " + j, _workbook_data[ j ],
                             buffer[ j ]);
            }
            for (int j = offset + _buffer_size; j < buffer.length; j++)
            {
                assertEquals("checking byte " + j, 0, buffer[ j ]);
            }
            offset += _buffer_size;
            assertEquals("offset " + offset, _workbook_size - offset,
                         stream.available());
        }
        assertEquals(_workbook_size % _buffer_size, stream.available());
        Arrays.fill(buffer, ( byte ) 0);
        int count = stream.read(buffer, offset,
                                _workbook_size % _buffer_size);

        assertEquals(_workbook_size % _buffer_size, count);
        for (int j = 0; j < offset; j++)
        {
            assertEquals("checking byte " + j, 0, buffer[ j ]);
        }
        for (int j = offset; j < buffer.length; j++)
        {
            assertEquals("checking byte " + j, _workbook_data[ j ],
                         buffer[ j ]);
        }
        assertEquals(_workbook_size, offset + count);
        for (int j = count; j < offset; j++)
        {
            assertEquals("byte " + j, 0, buffer[ j ]);
        }
        assertEquals(-1, stream.read(buffer, 0, 1));
        stream.close();
        try
        {
            stream.read(buffer, 0, 1);
            fail("Should have caught IOException");
        }
        catch (IOException ignored)
        {

            // as expected
        }
    }

    /**
     * test skip
     *
     * @exception IOException
     */

    public void testSkip()
        throws IOException
    {
        DocumentInputStream stream = new DocumentInputStream(_workbook);

        assertEquals(_workbook_size, stream.available());
        int count = stream.available();

        while (stream.available() >= _buffer_size)
        {
            assertEquals(_buffer_size, stream.skip(_buffer_size));
            count -= _buffer_size;
            assertEquals(count, stream.available());
        }
        assertEquals(_workbook_size % _buffer_size,
                     stream.skip(_buffer_size));
        assertEquals(0, stream.available());
        stream.reset();
        assertEquals(_workbook_size, stream.available());
        assertEquals(_workbook_size, stream.skip(_workbook_size * 2));
        assertEquals(0, stream.available());
        stream.reset();
        assertEquals(_workbook_size, stream.available());
        assertEquals(_workbook_size,
                     stream.skip(2 + ( long ) Integer.MAX_VALUE));
        assertEquals(0, stream.available());
    }

    /**
     * main method to run the unit tests
     *
     * @param ignored_args
     */

    public static void main(String [] ignored_args)
    {
        System.out.println(
            "Testing org.apache.poi.poifs.filesystem.DocumentInputStream");
        junit.textui.TestRunner.run(TestDocumentInputStream.class);
    }
}