PC Professionell 2004 December/PCpro_2004_12.ISO/files/webserver/xampp/xampp-tomcat-addon-1.4.9-installer.exe/CompressionResponseStream.class

Java Class File | 2004-05-17 | 4.1 KB | 173 lines

package compressionFilters;

import java.io.IOException;
import java.util.zip.GZIPOutputStream;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;

public class CompressionResponseStream extends ServletOutputStream {
   protected int compressionThreshold = 0;
   private int debug = 0;
   protected byte[] buffer = null;
   protected int bufferCount = 0;
   protected GZIPOutputStream gzipstream = null;
   protected boolean closed = false;
   protected int length = -1;
   protected HttpServletResponse response = null;
   protected ServletOutputStream output = null;

   public CompressionResponseStream(HttpServletResponse response) throws IOException {
      this.closed = false;
      this.response = response;
      this.output = response.getOutputStream();
   }

   public void setDebugLevel(int debug) {
      this.debug = debug;
   }

   protected void setBuffer(int threshold) {
      this.compressionThreshold = threshold;
      this.buffer = new byte[this.compressionThreshold];
      if (this.debug > 1) {
         System.out.println("buffer is set to " + this.compressionThreshold);
      }

   }

   public void close() throws IOException {
      if (this.debug > 1) {
         System.out.println("close() @ CompressionResponseStream");
      }

      if (this.closed) {
         throw new IOException("This output stream has already been closed");
      } else {
         if (this.gzipstream != null) {
            this.flushToGZip();
            this.gzipstream.close();
            this.gzipstream = null;
         } else if (this.bufferCount > 0) {
            if (this.debug > 2) {
               System.out.print("output.write(");
               System.out.write(this.buffer, 0, this.bufferCount);
               System.out.println(")");
            }

            this.output.write(this.buffer, 0, this.bufferCount);
            this.bufferCount = 0;
         }

         this.output.close();
         this.closed = true;
      }
   }

   public void flush() throws IOException {
      if (this.debug > 1) {
         System.out.println("flush() @ CompressionResponseStream");
      }

      if (this.closed) {
         throw new IOException("Cannot flush a closed output stream");
      } else {
         if (this.gzipstream != null) {
            this.gzipstream.flush();
         }

      }
   }

   public void flushToGZip() throws IOException {
      if (this.debug > 1) {
         System.out.println("flushToGZip() @ CompressionResponseStream");
      }

      if (this.bufferCount > 0) {
         if (this.debug > 1) {
            System.out.println("flushing out to GZipStream, bufferCount = " + this.bufferCount);
         }

         this.writeToGZip(this.buffer, 0, this.bufferCount);
         this.bufferCount = 0;
      }

   }

   public void write(int b) throws IOException {
      if (this.debug > 1) {
         System.out.println("write " + b + " in CompressionResponseStream ");
      }

      if (this.closed) {
         throw new IOException("Cannot write to a closed output stream");
      } else {
         if (this.bufferCount >= this.buffer.length) {
            this.flushToGZip();
         }

         this.buffer[this.bufferCount++] = (byte)b;
      }
   }

   public void write(byte[] b) throws IOException {
      this.write(b, 0, b.length);
   }

   public void write(byte[] b, int off, int len) throws IOException {
      if (this.debug > 1) {
         System.out.println("write, bufferCount = " + this.bufferCount + " len = " + len + " off = " + off);
      }

      if (this.debug > 2) {
         System.out.print("write(");
         System.out.write(b, off, len);
         System.out.println(")");
      }

      if (this.closed) {
         throw new IOException("Cannot write to a closed output stream");
      } else if (len != 0) {
         if (len <= this.buffer.length - this.bufferCount) {
            System.arraycopy(b, off, this.buffer, this.bufferCount, len);
            this.bufferCount += len;
         } else {
            this.flushToGZip();
            if (len <= this.buffer.length - this.bufferCount) {
               System.arraycopy(b, off, this.buffer, this.bufferCount, len);
               this.bufferCount += len;
            } else {
               this.writeToGZip(b, off, len);
            }
         }
      }
   }

   public void writeToGZip(byte[] b, int off, int len) throws IOException {
      if (this.debug > 1) {
         System.out.println("writeToGZip, len = " + len);
      }

      if (this.debug > 2) {
         System.out.print("writeToGZip(");
         System.out.write(b, off, len);
         System.out.println(")");
      }

      if (this.gzipstream == null) {
         if (this.debug > 1) {
            System.out.println("new GZIPOutputStream");
         }

         this.response.addHeader("Content-Encoding", "gzip");
         this.gzipstream = new GZIPOutputStream(this.output);
      }

      this.gzipstream.write(b, off, len);
   }

   public boolean closed() {
      return this.closed;
   }
}