| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.iapi.services.io.ArrayOutputStream |
| 4 | |
| 5 | Copyright 1998, 2004 The Apache Software Foundation or its licensors, as applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | |
| 21 | package org.apache.derby.iapi.services.io; |
| 22 | |
| 23 | import java.io.IOException; |
| 24 | import java.io.EOFException; |
| 25 | import java.io.OutputStream; |
| 26 | |
| 27 | public class ArrayOutputStream extends OutputStream implements Limit { |
| 28 | |
| 29 | private byte[] pageData; |
| 30 | |
| 31 | private int start; |
| 32 | private int end; // exclusive |
| 33 | private int position; |
| 34 | |
| 35 | public ArrayOutputStream() { |
| 36 | super(); |
| 37 | } |
| 38 | |
| 39 | public ArrayOutputStream(byte[] data) { |
| 40 | super(); |
| 41 | setData(data); |
| 42 | } |
| 43 | |
| 44 | public void setData(byte[] data) { |
| 45 | pageData = data; |
| 46 | start = 0; |
| 47 | if (data != null) |
| 48 | end = data.length; |
| 49 | else |
| 50 | end = 0; |
| 51 | position = 0; |
| 52 | |
| 53 | } |
| 54 | |
| 55 | /* |
| 56 | ** Methods of OutputStream |
| 57 | */ |
| 58 | |
| 59 | public void write(int b) throws IOException { |
| 60 | if (position >= end) |
| 61 | throw new EOFException(); |
| 62 | |
| 63 | pageData[position++] = (byte) b; |
| 64 | |
| 65 | } |
| 66 | |
| 67 | public void write(byte b[], int off, int len) throws IOException { |
| 68 | |
| 69 | if ((position + len) > end) |
| 70 | throw new EOFException(); |
| 71 | |
| 72 | System.arraycopy(b, off, pageData, position, len); |
| 73 | position += len; |
| 74 | } |
| 75 | |
| 76 | /* |
| 77 | ** Methods of LengthOutputStream |
| 78 | */ |
| 79 | |
| 80 | public int getPosition() { |
| 81 | return position; |
| 82 | } |
| 83 | |
| 84 | /** |
| 85 | Set the position of the stream pointer. |
| 86 | */ |
| 87 | public void setPosition(int newPosition) |
| 88 | throws IOException { |
| 89 | if ((newPosition < start) || (newPosition > end)) |
| 90 | throw new EOFException(); |
| 91 | |
| 92 | position = newPosition; |
| 93 | } |
| 94 | |
| 95 | public void setLimit(int length) throws IOException { |
| 96 | |
| 97 | if (length < 0) { |
| 98 | throw new EOFException(); |
| 99 | } |
| 100 | |
| 101 | if ((position + length) > end) { |
| 102 | throw new EOFException(); |
| 103 | } |
| 104 | |
| 105 | start = position; |
| 106 | end = position + length; |
| 107 | |
| 108 | return; |
| 109 | } |
| 110 | |
| 111 | public int clearLimit() { |
| 112 | |
| 113 | int unwritten = end - position; |
| 114 | |
| 115 | end = pageData.length; |
| 116 | |
| 117 | return unwritten; |
| 118 | } |
| 119 | } |