SSLEngineDataStream.java revision 6b811c5daec1b28e6f63b57f98a032236f2c3cf7 
1/*
2 *  Licensed to the Apache Software Foundation (ASF) under one or more
3 *  contributor license agreements.  See the NOTICE file distributed with
4 *  this work for additional information regarding copyright ownership.
5 *  The ASF licenses this file to You under the Apache License, Version 2.0
6 *  (the "License"); you may not use this file except in compliance with
7 *  the License.  You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 *  Unless required by applicable law or agreed to in writing, software
12 *  distributed under the License is distributed on an "AS IS" BASIS,
13 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 *  See the License for the specific language governing permissions and
15 *  limitations under the License.
16 */
17
18package org.apache.harmony.xnet.provider.jsse;
19
20import java.nio.ByteBuffer;
21
22/**
23 * This class provides the DataStream functionality
24 * implemented over the array of ByteBuffer instances.
25 * Among with the data chunks read functionality
26 * it provides the info about amount of consumed data.
27 * The source ByteBuffer objects can be replaced by other.
28 * So one instance of this wrapper can be reused for several
29 * data sources.
30 */
31public class SSLEngineDataStream implements DataStream {
32
33    private ByteBuffer[] srcs;
34    private int offset;
35    private int limit;
36
37    private int available;
38    private int consumed;
39
40    protected SSLEngineDataStream() {}
41
42    protected void setSourceBuffers(ByteBuffer[] srcs, int offset, int length) {
43        this.srcs = srcs;
44        this.offset = offset;
45        this.limit = offset+length;
46        this.consumed = 0;
47        this.available = 0;
48        for (int i=offset; i<limit; i++) {
49            if (srcs[i] == null) {
50                throw new IllegalStateException(
51                        "Some of the input parameters are null");
52            }
53            available += srcs[i].remaining();
54        }
55    }
56
57    public int available() {
58        return available;
59    }
60
61    public boolean hasData() {
62        return available > 0;
63    }
64
65    public byte[] getData(int length) {
66        // TODO: optimization work:
67        // use ByteBuffer.get(byte[],int,int)
68        // and ByteBuffer.hasArray() methods
69        int len = (length < available) ? length : available;
70        available -= len;
71        consumed += len;
72        byte[] res = new byte[len];
73        int pos = 0;
74        loop:
75        for (; offset<limit; offset++) {
76            while (srcs[offset].hasRemaining()) {
77                res[pos++] = srcs[offset].get();
78                len --;
79                if (len == 0) {
80                    break loop;
81                }
82            }
83        }
84        return res;
85    }
86
87    protected int consumed() {
88        return consumed;
89    }
90}
91
92