source: josm/trunk/src/org/openstreetmap/josm/io/MultiPartFormOutputStream.java@ 2646

/*
Taken from forum.java.sun.com

License

Copyright 1994-2007 Sun Microsystems, Inc. All Rights Reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

 * Redistribution of source code must retain the above copyright notice, this list
      of conditions and the following disclaimer.

 * Redistribution in binary form must reproduce the above copyright notice, this
      list of conditions and the following disclaimer in the documentation and/or other
      materials provided with the distribution.

Neither the name of Sun Microsystems, Inc. or the names of contributors may be used to
endorse or promote products derived from this software without specific prior written
permission.

This software is provided "AS IS," without a warranty of any kind. ALL EXPRESS OR IMPLIED
CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS,
INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS
A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT
WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT,
INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS
SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

You acknowledge that this software is not designed, licensed or intended for use in the
design, construction, operation or maintenance of any nuclear facility.
 */

package org.openstreetmap.josm.io;

import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;

/**
 * <code>MultiPartFormOutputStream</code> is used to write
 * "multipart/form-data" to a <code>java.net.URLConnection</code> for
 * POSTing.  This is primarily for file uploading to HTTP servers.
 *
 * @since  JDK1.3
 */
public class MultiPartFormOutputStream extends OsmConnection {
    /**
     * The line end characters.
     */
    private static final String NEWLINE = "\r\n";

    /**
     * The boundary prefix.
     */
    private static final String PREFIX = "--";

    /**
     * The output stream to write to.
     */
    private DataOutputStream out = null;

    /**
     * The multipart boundary string.
     */
    private String boundary = null;

    /**
     * Creates a new <code>MultiPartFormOutputStream</code> object using
     * the specified output stream and boundary.  The boundary is required
     * to be created before using this method, as described in the
     * description for the <code>getContentType(String)</code> method.
     * The boundary is only checked for <code>null</code> or empty string,
     * but it is recommended to be at least 6 characters.  (Or use the
     * static createBoundary() method to create one.)
     *
     * @param  os        the output stream
     * @param  boundary  the boundary
     * @see  #createBoundary()
     * @see  #getContentType(String)
     */
    public MultiPartFormOutputStream(OutputStream os, String boundary) {
        if(os == null)
            throw new IllegalArgumentException("Output stream is required.");
        if(boundary == null || boundary.length() == 0)
            throw new IllegalArgumentException("Boundary stream is required.");
        this.out = new DataOutputStream(os);
        this.boundary = boundary;
    }

    /**
     * Writes an boolean field value.
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, boolean value)
    throws java.io.IOException {
        writeField(name, Boolean.valueOf(value).toString());
    }

    /**
     * Writes an double field value.
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, double value)
    throws java.io.IOException {
        writeField(name, Double.toString(value));
    }

    /**
     * Writes an float field value.
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, float value)
    throws java.io.IOException {
        writeField(name, Float.toString(value));
    }

    /**
     * Writes an long field value.
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, long value)
    throws java.io.IOException {
        writeField(name, Long.toString(value));
    }

    /**
     * Writes an int field value.
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, int value)
    throws java.io.IOException {
        writeField(name, Integer.toString(value));
    }

    /**
     * Writes an short field value.
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, short value)
    throws java.io.IOException {
        writeField(name, Short.toString(value));
    }

    /**
     * Writes an char field value.
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, char value)
    throws java.io.IOException {
        writeField(name, Character.valueOf(value).toString());
    }

    /**
     * Writes an string field value.  If the value is null, an empty string
     * is sent ("").
     *
     * @param  name   the field name (required)
     * @param  value  the field value
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeField(String name, String value)
    throws java.io.IOException {
        if(name == null)
            throw new IllegalArgumentException("Name cannot be null or empty.");
        if(value == null) {
            value = "";
        }
        /*
            --boundary\r\n
            Content-Disposition: form-data; name="<fieldName>"\r\n
            \r\n
            <value>\r\n
         */
        // write boundary
        out.writeBytes(PREFIX);
        out.writeBytes(boundary);
        out.writeBytes(NEWLINE);
        // write content header
        out.writeBytes("Content-Disposition: form-data; name=\"" + name + "\"");
        out.writeBytes(NEWLINE);
        out.writeBytes(NEWLINE);
        // write content
        out.writeBytes(value);
        out.writeBytes(NEWLINE);
        out.flush();
    }

    /**
     * Writes a file's contents.  If the file is null, does not exists, or
     * is a directory, a <code>java.lang.IllegalArgumentException</code>
     * will be thrown.
     *
     * @param  name      the field name
     * @param  mimeType  the file content type (optional, recommended)
     * @param  file      the file (the file must exist)
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeFile(String name, String mimeType, java.io.File file)
    throws java.io.IOException {
        if(file == null)
            throw new IllegalArgumentException("File cannot be null.");
        if(!file.exists())
            throw new IllegalArgumentException("File does not exist.");
        if(file.isDirectory())
            throw new IllegalArgumentException("File cannot be a directory.");
        writeFile(name, mimeType, file.getCanonicalPath(), new FileInputStream(file));
    }

    /**
     * Writes a input stream's contents.  If the input stream is null, a
     * <code>java.lang.IllegalArgumentException</code> will be thrown.
     *
     * @param  name      the field name
     * @param  mimeType  the file content type (optional, recommended)
     * @param  fileName  the file name (required)
     * @param  is        the input stream
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeFile(String name, String mimeType,
            String fileName, InputStream is)
    throws java.io.IOException {
        if(is == null)
            throw new IllegalArgumentException("Input stream cannot be null.");
        if(fileName == null || fileName.length() == 0)
            throw new IllegalArgumentException("File name cannot be null or empty.");
        /*
            --boundary\r\n
            Content-Disposition: form-data; name="<fieldName>"; filename="<filename>"\r\n
            Content-Type: <mime-type>\r\n
            \r\n
            <file-data>\r\n
         */
        // write boundary
        out.writeBytes(PREFIX);
        out.writeBytes(boundary);
        out.writeBytes(NEWLINE);
        // write content header
        out.writeBytes("Content-Disposition: form-data; name=\"" + name +
                "\"; filename=\"" + fileName + "\"");
        out.writeBytes(NEWLINE);
        if(mimeType != null) {
            out.writeBytes("Content-Type: " + mimeType);
            out.writeBytes(NEWLINE);
        }
        out.writeBytes(NEWLINE);
        // write content
        byte[] data = new byte[1024];
        int r = 0;
        while((r = is.read(data, 0, data.length)) != -1) {
            out.write(data, 0, r);
        }
        // close input stream, but ignore any possible exception for it
        try {
            is.close();
        } catch(Exception e) {}
        out.writeBytes(NEWLINE);
        out.flush();
    }

    /**
     * Writes the given bytes.  The bytes are assumed to be the contents
     * of a file, and will be sent as such.  If the data is null, a
     * <code>java.lang.IllegalArgumentException</code> will be thrown.
     *
     * @param  name      the field name
     * @param  mimeType  the file content type (optional, recommended)
     * @param  fileName  the file name (required)
     * @param  data      the file data
     * @throws  java.io.IOException  on input/output errors
     */
    public void writeFile(String name, String mimeType,
            String fileName, byte[] data)
    throws java.io.IOException {
        if(data == null)
            throw new IllegalArgumentException("Data cannot be null.");
        if(fileName == null || fileName.length() == 0)
            throw new IllegalArgumentException("File name cannot be null or empty.");
        /*
            --boundary\r\n
            Content-Disposition: form-data; name="<fieldName>"; filename="<filename>"\r\n
            Content-Type: <mime-type>\r\n
            \r\n
            <file-data>\r\n
         */
        // write boundary
        out.writeBytes(PREFIX);
        out.writeBytes(boundary);
        out.writeBytes(NEWLINE);
        // write content header
        out.writeBytes("Content-Disposition: form-data; name=\"" + name +
                "\"; filename=\"" + fileName + "\"");
        out.writeBytes(NEWLINE);
        if(mimeType != null) {
            out.writeBytes("Content-Type: " + mimeType);
            out.writeBytes(NEWLINE);
        }
        out.writeBytes(NEWLINE);
        // write content
        out.write(data, 0, data.length);
        out.writeBytes(NEWLINE);
        out.flush();
    }

    /**
     * Flushes the stream.  Actually, this method does nothing, as the only
     * write methods are highly specialized and automatically flush.
     */
    public void flush() {
        // out.flush();
    }

    /**
     * Closes the stream.  <br/>
     * <br/>
     * <b>NOTE:</b> This method <b>MUST</b> be called to finalize the
     * multipart stream.
     *
     * @throws  java.io.IOException  on input/output errors
     */
    public void close() throws java.io.IOException {
        // write final boundary
        out.writeBytes(PREFIX);
        out.writeBytes(boundary);
        out.writeBytes(PREFIX);
        out.writeBytes(NEWLINE);
        out.flush();
        out.close();
    }

    /**
     * Gets the multipart boundary string being used by this stream.
     *
     * @return  the boundary
     */
    public String getBoundary() {
        return this.boundary;
    }

    /**
     * Creates a new <code>java.net.URLConnection</code> object from the
     * specified <code>java.net.URL</code>.  This is a convenience method
     * which will set the <code>doInput</code>, <code>doOutput</code>,
     * <code>useCaches</code> and <code>defaultUseCaches</code> fields to
     * the appropriate settings in the correct order.
     *
     * @return  a <code>java.net.URLConnection</code> object for the URL
     * @throws  java.io.IOException  on input/output errors
     */
    public static URLConnection createConnection(URL url)
    throws java.io.IOException {
        URLConnection urlConn = url.openConnection();
        if(urlConn instanceof HttpURLConnection) {
            HttpURLConnection httpConn = (HttpURLConnection)urlConn;
            httpConn.setRequestMethod("POST");
        }
        urlConn.setDoInput(true);
        urlConn.setDoOutput(true);
        urlConn.setUseCaches(false);
        urlConn.setDefaultUseCaches(false);
        return urlConn;
    }

    /**
     * Creates a multipart boundary string by concatenating 20 hyphens (-)
     * and the hexadecimal (base-16) representation of the current time in
     * milliseconds.
     *
     * @return  a multipart boundary string
     * @see  #getContentType(String)
     */
    public static String createBoundary() {
        return "--------------------" +
        Long.toString(System.currentTimeMillis(), 16);
    }

    /**
     * Gets the content type string suitable for the
     * <code>java.net.URLConnection</code> which includes the multipart
     * boundary string.  <br/>
     * <br/>
     * This method is static because, due to the nature of the
     * <code>java.net.URLConnection</code> class, once the output stream
     * for the connection is acquired, it's too late to set the content
     * type (or any other request parameter).  So one has to create a
     * multipart boundary string first before using this class, such as
     * with the <code>createBoundary()</code> method.
     *
     * @param  boundary  the boundary string
     * @return  the content type string
     * @see  #createBoundary()
     */
    public static String getContentType(String boundary) {
        return "multipart/form-data; boundary=" + boundary;
    }
}