ZipDecoderService.java :  » XML-UI » xui32 » com » xoetrope » service » Java Open Source

package com.xoetrope.service;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Vector;
import java.util.zip.Adler32;
import java.util.zip.CheckedInputStream;
import java.util.zip.CheckedOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

import net.xoetrope.debug.DebugLogger;
import net.xoetrope.optional.service.ServiceProxy;
import net.xoetrope.optional.service.ServiceProxyException;
import com.xoetrope.carousel.build.BuildProperties;
import java.util.Hashtable;
import net.xoetrope.optional.service.ServiceContext;
import net.xoetrope.optional.service.ServiceProxyArgs;

/**
 * Compresses the output data in a zip stream
 *
 * <p> Copyright (c) Xoetrope Ltd., 2001-2006, This software is licensed under
 * the GNU Public License (GPL), please see license.txt for more details. If
 * you make commercial use of this software you must purchase a commercial
 * license from Xoetrope.</p>
 * <p> $Revision: 1.9 $</p>
 */
public class ZipDecoderService extends ServiceProxy
{
  public ZipDecoderService()
  {
    status = OK;
  }

  /**
   * Deompresses the call, its arguments using the ZLib zip algorithm. The
   * response is compressed. The call is then forwarded to the
   * next service proxy in the chain.
   * @param method the method name to be invoked
   * @param context the context of the service call
   * @return the response or result of the call
   * @throws ServiceProxyException
   */
  public Object call( String method, ServiceContext context ) throws ServiceProxyException
  {
    try {
      status = STARTED;
      //int numArgs = args.getNumArgs();
      ServiceProxyArgs args = context.getArgs();

        // Decompress the output.
      if ( BuildProperties.DEBUG ) {
        if ( args.getPassParam( "ZipStream" ) == null ) {
          DebugLogger.logError( "Invalid ZipDecoderService argument" );
          throw new ServiceProxyException( "Invalid ZipDecoderService argument" );
        }
      }

      ByteArrayInputStream bis = new ByteArrayInputStream( org.apache.catalina.util.Base64.decode( ((String)args.getPassParam( "ZipStream" )).getBytes() ));
      CheckedInputStream cis = new CheckedInputStream( bis, new Adler32() );
      ZipInputStream zis = new ZipInputStream( cis );
      Vector zipArgNames = new Vector();
      Vector zipArgValues = new Vector();

      final int BUFFER_SIZE = 2048;
      int count;
      byte[] buf = new byte[ BUFFER_SIZE ];
      ZipEntry ze;
      while ( ( ze = zis.getNextEntry() ) != null ) {
        zipArgNames.addElement( ze.getName() );
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        while ( ( zis.available() > 0 ) && ( ( count = zis.read( buf, 0, BUFFER_SIZE ) ) != -1 ) )
          bos.write( buf, 0, count );

        zipArgValues.addElement( new String( bos.toByteArray() ) );
      }

      // Call the next service proxy
      ServiceContext callContext = new ServiceContext();
      Hashtable passArgs = callContext.getPassArgs();
      passArgs.clear();
      int numDecodedArgs = zipArgNames.size();
      String decodedArgNames[] = new String[ numDecodedArgs ];
      for ( int k = 0; k < numDecodedArgs; k++ )
        passArgs.put( (String)zipArgNames.elementAt( k ), zipArgValues.elementAt( k ));
      
      Object status = nextProxy.call( method, callContext );
      Object result = callContext.getReturnArgs().get( ServiceProxy.RETURN_VALUE );

      ByteArrayOutputStream bos = new ByteArrayOutputStream();
      CheckedOutputStream cos = new CheckedOutputStream( bos, new Adler32() );
      ZipOutputStream zos = new ZipOutputStream( cos );

      // Create a new entry and output
      if ( result != null ) {
        ZipEntry zeOut = new ZipEntry( "ZipStream" );
        zos.putNextEntry( zeOut );
        zos.write( result.toString().getBytes());
        zeOut.setCrc( cos.getChecksum().getValue() );
      }
      zos.close();

      status = COMPLETE;
      context.setReturnValue( new String( org.apache.catalina.util.Base64.encode( bos.toByteArray())));
      return status;
    }
    catch ( IOException ioex ) {
      status = FAILED;
      if ( BuildProperties.DEBUG )
        ioex.printStackTrace();
    }
    catch ( ServiceProxyException ex ) {
      status = FAILED;
      throw ( ex );
    }

    return null;
  }
}