managedmemorydatasource.java

Java有关XML编程需要用到axis 的源代码 把里面bin下的包导入相应的Java工程 进行使用

/*
 * Copyright 2001-2004 The Apache Software Foundation.
 * 
 * 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 org.apache.axis.attachments;

import org.apache.axis.InternalException;
import org.apache.axis.MessageContext;
import org.apache.axis.components.logger.LogFactory;
import org.apache.axis.utils.Messages;
import org.apache.commons.logging.Log;

import java.io.File;
import java.io.BufferedInputStream;

/**
 * This class allows small attachments to be cached in memory, while large ones are
 * cached out.  It implements a Java Activiation Data source interface.
 *
 * @author Rick Rineholt
 */
public class ManagedMemoryDataSource implements javax.activation.DataSource {

    /** Field log           */
    protected static Log log =
         LogFactory.getLog(ManagedMemoryDataSource.class.getName());

    /**
     * The content type. This defaults to
     * <code>application/octet-stream</code>.
     */
    protected String contentType = "application/octet-stream";

    /** The incoming source stream. */
    java.io.InputStream ss = null;

    /** Field MIN_MEMORY_DISK_CACHED           */
    public static final int MIN_MEMORY_DISK_CACHED = -1;

    /** Field MAX_MEMORY_DISK_CACHED           */
    public static final int MAX_MEMORY_DISK_CACHED = 16 * 1024;

    /** Field maxCached           */
    protected int maxCached = MAX_MEMORY_DISK_CACHED;       // max in memory cached. Default.

    // If set the file the disk is cached to.

    /** Field diskCacheFile           */
    protected java.io.File diskCacheFile = null;

    // A list of open input Streams.

    /** Field readers           */
    protected java.util.WeakHashMap readers = new java.util.WeakHashMap();

    /**
     * Flag to show if the resources behind this have been deleted.
     */
    protected boolean deleted =
            false;

    // Memory is allocated in these size chunks.

    /** Field READ_CHUNK_SZ           */
    public static final int READ_CHUNK_SZ = 32 * 1024;

    /** Field debugEnabled           */
    protected boolean debugEnabled = false;    // Log debugging if true.

    // Should not be called;

    /**
     * Constructor ManagedMemoryDataSource.
     */
    protected ManagedMemoryDataSource() {
    }

    /**
     * Create a new boundary stream.
     *
     * @param ss is the source input stream that is used to create this data source.
     * @param maxCached  This is the max memory that is to be used to cache the data.
     * @param contentType the mime type for this data stream.
     *   by buffering you can some effiency in searching.
     *
     * @throws java.io.IOException
     */
    public ManagedMemoryDataSource(
            java.io.InputStream ss, int maxCached, String contentType)
            throws java.io.IOException {
        this(ss, maxCached, contentType, false);
    }

    /**
     * Create a new boundary stream.
     *
     * @param ss is the source input stream that is used to create this data source.
     * @param maxCached  This is the max memory that is to be used to cache the data.
     * @param contentType the mime type for this data stream.
     *   by buffering you can some effiency in searching.
     * @param readall if true will read in the whole source.
     *
     * @throws java.io.IOException
     */
    public ManagedMemoryDataSource(
            java.io.InputStream ss, int maxCached, String contentType, boolean readall)
            throws java.io.IOException {

        if(ss instanceof BufferedInputStream) {
            this.ss = ss;
        } else {
            this.ss = new BufferedInputStream(ss);
        }
        this.maxCached = maxCached;

        if ((null != contentType) && (contentType.length() != 0)) {
            this.contentType = contentType;
        }

        if (maxCached < MIN_MEMORY_DISK_CACHED) {
            throw new IllegalArgumentException(
                    Messages.getMessage("badMaxCached", "" + maxCached));
        }

        if (log.isDebugEnabled()) {
            debugEnabled = true;    // Logging should be initialized by time;
        }

        // for now read all in to disk.
        if (readall) {
            byte[] readbuffer = new byte[READ_CHUNK_SZ];
            int read = 0;

            do {
                read = ss.read(readbuffer);

                if (read > 0) {
                    write(readbuffer, read);
                }
            } while (read > -1);

            close();
        }
    }

    /* javax.activation.Interface DataSource implementation */

    /**
     * This method returns the MIME type of the data in the form of a string.
     * @return The mime type.
     */
    public java.lang.String getContentType() {
        return contentType;
    }

    /**
     * This method returns an InputStream representing the the data and throws the appropriate exception if it can not do so.
     * @return the java.io.InputStream for the data source.
     *
     * @throws java.io.IOException
     */
    public synchronized java.io.InputStream getInputStream()
            throws java.io.IOException {

        /*
         * if (memorybuflist == null) {
         *   return  new java.io.FileInputStream(diskCacheFile);
         * }
         * else
         */
        return new Instream();    // Return the memory held stream.
    }

    /**
     * This will flush any memory source to disk and
     * provide the name of the file if desired.
     *
     * @return the name of the file of the stream
     */
    public java.lang.String getName() {

        String ret = null;

        try {
            flushToDisk();

            if (diskCacheFile != null) {
                ret = diskCacheFile.getAbsolutePath();
            }
        } catch (Exception e) {
            diskCacheFile = null;
        }

        return ret;
    }

    /**
     * This method returns an OutputStream where the data can be written and
     * throws the appropriate exception if it can not do so.
     * NOT SUPPORTED, not need for axis, data sources are create by constructors.
     *
     *
     * @return always <code>null</code>
     *
     * @throws java.io.IOException
     */
    public java.io.OutputStream getOutputStream() throws java.io.IOException {
        return null;
    }

    /** The linked list to hold the in memory buffers. */
    protected java.util.LinkedList memorybuflist =
            new java.util.LinkedList();

    /** Hold the last memory buffer. */
    protected byte[] currentMemoryBuf = null;

    /** The number of bytes written to the above buffer. */
    protected int currentMemoryBufSz =
            0;

    /** The total size in bytes in this data source. */
    protected long totalsz = 0;

    /** This is the cached disk stream. */
    protected java.io.BufferedOutputStream cachediskstream =
            null;

    /** If true the source input stream is now closed. */
    protected boolean closed = false;

    /**
     * Write bytes to the stream.
     *
     * @param data all bytes of this array are written to the stream
     * @throws java.io.IOException if there was a problem writing the data
     */
    protected void write(byte[] data) throws java.io.IOException {
        write(data, data.length);
    }

    /**
     * This method is a low level write.
     * Note it is designed to in the future to allow streaming to both memory
     *  AND to disk simultaneously.
     *
     * @param data
     * @param length
     *
     * @throws java.io.IOException
     */
    protected synchronized void write(byte[] data, int length)
            throws java.io.IOException {

        if (closed) {
            throw new java.io.IOException(Messages.getMessage("streamClosed"));
        }

        int writesz = length;
        int byteswritten = 0;

        if ((null != memorybuflist)
                && (totalsz + writesz > maxCached)) {    // Cache to disk.
            if (null == cachediskstream) {               // Need to create a disk cache
                flushToDisk();
            }
        }

        if (memorybuflist != null) {    // Can write to memory.
            do {
                if (null == currentMemoryBuf) {
                    currentMemoryBuf = new byte[READ_CHUNK_SZ];
                    currentMemoryBufSz = 0;

                    memorybuflist.add(currentMemoryBuf);
                }

                // bytes to write is the min. between the remaining bytes and what is left in this buffer.
                int bytes2write = Math.min((writesz - byteswritten),
                        (currentMemoryBuf.length
                        - currentMemoryBufSz));

                // copy the data.
                System.arraycopy(data, byteswritten, currentMemoryBuf,
                        currentMemoryBufSz, bytes2write);

                byteswritten += bytes2write;
                currentMemoryBufSz += bytes2write;

                if (byteswritten
                        < writesz) {    // only get more if we really need it.
                    currentMemoryBuf = new byte[READ_CHUNK_SZ];
                    currentMemoryBufSz = 0;

                    memorybuflist.add(currentMemoryBuf);    // add it to the chain.
                }
            } while (byteswritten < writesz);
        }

        if (null != cachediskstream) {    // Write to the out going stream.
            cachediskstream.write(data, 0, length);
        }

        totalsz += writesz;

        return;
    }

    /**
     * This method is a low level write.
     * Close the stream.
     *
     * @throws java.io.IOException
     */
    protected synchronized void close() throws java.io.IOException {

        if (!closed) {
            closed = true;                    // Markit as closed.

            if (null != cachediskstream) {    // close the disk cache.
                cachediskstream.close();

                cachediskstream = null;
            }

            if (null != memorybuflist) {      // There is a memory buffer.
                if (currentMemoryBufSz > 0) {
                    byte[] tmp =
                            new byte[currentMemoryBufSz];    // Get the last buffer and make it the sizeof the actual data.

                    System.arraycopy(currentMemoryBuf, 0, tmp, 0,
                            currentMemoryBufSz);
                    memorybuflist.set(
                            memorybuflist.size() - 1,
                            tmp);                 // Now replace the last buffer with this size.
                }

                currentMemoryBuf = null;      // No need for this anymore.
            }
        }
    }

    protected void finalize() throws Throwable {

        if (null != cachediskstream) {    // close the disk cache.
            cachediskstream.close();

            cachediskstream = null;
        }
    }

    /**
     * Routine to flush data to disk if is in memory.
     *
     * @throws java.io.IOException
     * @throws java.io.FileNotFoundException
     */
    protected void flushToDisk()
            throws java.io.IOException, java.io.FileNotFoundException {

        java.util.LinkedList ml = memorybuflist;

        log.debug(Messages.getMessage("maxCached", "" + maxCached,
                "" + totalsz));

        if (ml != null) {
            if (null == cachediskstream) {    // Need to create a disk cache
                try {
                    MessageContext mc = MessageContext.getCurrentContext();
                    String attdir = (mc == null)
                            ? null
                            : mc.getStrProp(
                                    MessageContext.ATTACHMENTS_DIR);

                    diskCacheFile = java.io.File.createTempFile("Axis", ".att",
                            (attdir == null)
                            ? null
                            : new File(
                                    attdir));

                    if(log.isDebugEnabled()) {
                        log.debug(
                            Messages.getMessage(
                                    "diskCache", diskCacheFile.getAbsolutePath()));
                     }

                    cachediskstream = new java.io.BufferedOutputStream(
                            new java.io.FileOutputStream(diskCacheFile));

                    int listsz = ml.size();

                    // Write out the entire memory held store to disk.
                    for (java.util.Iterator it = ml.iterator();
                         it.hasNext();) {
                        byte[] rbuf = (byte[]) it.next();
                        int bwrite = (listsz-- == 0)
                                ? currentMemoryBufSz
                                : rbuf.length;

                        cachediskstream.write(rbuf, 0, bwrite);

                        if (closed) {
                            cachediskstream.close();

                            cachediskstream = null;
                        }
                    }

                    memorybuflist = null;
                } catch (java.lang.SecurityException se) {
                    diskCacheFile = null;
                    cachediskstream = null;
                    maxCached = java.lang.Integer.MAX_VALUE;

                    log.info(Messages.getMessage("nodisk00"), se);
                }
            }
        }
    }

    public synchronized boolean delete() {

        boolean ret = false;

        deleted = true;

        memorybuflist = null;

        if (diskCacheFile != null) {
            if (cachediskstream != null) {
                try {
                    cachediskstream.close();
                } catch (Exception e) {
                }

                cachediskstream = null;
            }