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Utility functions related to Streams

/*  * Licensed to the Apache Software Foundation (ASF) under one or more  * 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,  * 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.  */ import java.io.ByteArrayOutputStream; import java.io.InputStream; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.Reader; import java.io.Writer; import java.io.InputStreamReader; /**  * Utility functions related to Streams.  *  * @author <a href="mailto:taylor@apache.org">David Sean Taylor</a>  * @version $Id: Streams.java 516448 2007-03-09 16:25:47Z ate $  */ public class Streams {   static final int BLOCK_SIZE=4096;   public static void drain(InputStream r,OutputStream w) throws IOException   {       byte[] bytes=new byte[BLOCK_SIZE];       try       {         int length=r.read(bytes);         while(length!=-1)         {             if(length!=0)                 {                     w.write(bytes,0,length);                 }             length=r.read(bytes);         }     }     finally     {       bytes=null;     }   }   public static void drain(Reader r,Writer w) throws IOException   {     char[] bytes=new char[BLOCK_SIZE];     try     {         int length=r.read(bytes);         while(length!=-1)         {             if(length!=0)             {                 w.write(bytes,0,length);             }             length=r.read(bytes);         }     }     finally     {         bytes=null;     }   }   public static void drain(Reader r,OutputStream os) throws IOException   {         Writer w=new OutputStreamWriter(os);         drain(r,w);         w.flush();   }   public static void drain(InputStream is, Writer w) throws IOException   {       Reader r = new InputStreamReader(is);       drain(r,w);       w.flush();   }   public static byte[] drain(InputStream r) throws IOException   {         ByteArrayOutputStream bytes=new ByteArrayOutputStream();         drain(r,bytes);         return bytes.toByteArray();   }   public static String getAsString(InputStream is)   {       int c=0;       char lineBuffer[]=new char[128], buf[]=lineBuffer;       int room= buf.length, offset=0;       try       {           loop: while (true)           {             // read chars into a buffer which grows as needed                 switch (c = is.read() )                 {                     case -1: break loop;                     default: if (--room < 0)                              {                                  buf = new char[offset + 128];                                  room = buf.length - offset - 1;                                  System.arraycopy(lineBuffer, 0,                                           buf, 0, offset);                                  lineBuffer = buf;                              }                              buf[offset++] = (char) c;                              break;                 }           }       }       catch(IOException ioe)       {           ioe.printStackTrace();       }       if ((c == -1) && (offset == 0))       {           return null;       }       return String.copyValueOf(buf, 0, offset);   } }