001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 018 package org.apache.geronimo.util.encoders; 019 020 021 /** 022 * a buffering class to allow translation from one format to another to 023 * be done in discrete chunks. 024 */ 025 public class BufferedEncoder 026 { 027 protected byte[] buf; 028 protected int bufOff; 029 030 protected Translator translator; 031 032 /** 033 * @param translator the translator to use. 034 * @param bufSize amount of input to buffer for each chunk. 035 */ 036 public BufferedEncoder( 037 Translator translator, 038 int bufSize) 039 { 040 this.translator = translator; 041 042 if ((bufSize % translator.getEncodedBlockSize()) != 0) 043 { 044 throw new IllegalArgumentException("buffer size not multiple of input block size"); 045 } 046 047 buf = new byte[bufSize]; 048 bufOff = 0; 049 } 050 051 public int processByte( 052 byte in, 053 byte[] out, 054 int outOff) 055 { 056 int resultLen = 0; 057 058 buf[bufOff++] = in; 059 060 if (bufOff == buf.length) 061 { 062 resultLen = translator.encode(buf, 0, buf.length, out, outOff); 063 bufOff = 0; 064 } 065 066 return resultLen; 067 } 068 069 public int processBytes( 070 byte[] in, 071 int inOff, 072 int len, 073 byte[] out, 074 int outOff) 075 { 076 if (len < 0) 077 { 078 throw new IllegalArgumentException("Can't have a negative input length!"); 079 } 080 081 int resultLen = 0; 082 int gapLen = buf.length - bufOff; 083 084 if (len > gapLen) 085 { 086 System.arraycopy(in, inOff, buf, bufOff, gapLen); 087 088 resultLen += translator.encode(buf, 0, buf.length, out, outOff); 089 090 bufOff = 0; 091 092 len -= gapLen; 093 inOff += gapLen; 094 outOff += resultLen; 095 096 int chunkSize = len - (len % buf.length); 097 098 resultLen += translator.encode(in, inOff, chunkSize, out, outOff); 099 100 len -= chunkSize; 101 inOff += chunkSize; 102 } 103 104 if (len != 0) 105 { 106 System.arraycopy(in, inOff, buf, bufOff, len); 107 108 bufOff += len; 109 } 110 111 return resultLen; 112 } 113 }