1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. 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,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.message;
29
30 /**
31 * This class represents a context of a parsing operation:
32 * <ul>
33 * <li>the current position the parsing operation is expected to start at</li>
34 * <li>the bounds limiting the scope of the parsing operation</li>
35 * </ul>
36 *
37 * @since 4.0
38 */
39 public class ParserCursor {
40
41 private final int lowerBound;
42 private final int upperBound;
43 private int pos;
44
45 public ParserCursor(final int lowerBound, final int upperBound) {
46 super();
47 if (lowerBound < 0) {
48 throw new IndexOutOfBoundsException("Lower bound cannot be negative");
49 }
50 if (lowerBound > upperBound) {
51 throw new IndexOutOfBoundsException("Lower bound cannot be greater then upper bound");
52 }
53 this.lowerBound = lowerBound;
54 this.upperBound = upperBound;
55 this.pos = lowerBound;
56 }
57
58 public int getLowerBound() {
59 return this.lowerBound;
60 }
61
62 public int getUpperBound() {
63 return this.upperBound;
64 }
65
66 public int getPos() {
67 return this.pos;
68 }
69
70 public void updatePos(final int pos) {
71 if (pos < this.lowerBound) {
72 throw new IndexOutOfBoundsException("pos: "+pos+" < lowerBound: "+this.lowerBound);
73 }
74 if (pos > this.upperBound) {
75 throw new IndexOutOfBoundsException("pos: "+pos+" > upperBound: "+this.upperBound);
76 }
77 this.pos = pos;
78 }
79
80 public boolean atEnd() {
81 return this.pos >= this.upperBound;
82 }
83
84 @Override
85 public String toString() {
86 final StringBuilder buffer = new StringBuilder();
87 buffer.append('[');
88 buffer.append(Integer.toString(this.lowerBound));
89 buffer.append('>');
90 buffer.append(Integer.toString(this.pos));
91 buffer.append('>');
92 buffer.append(Integer.toString(this.upperBound));
93 buffer.append(']');
94 return buffer.toString();
95 }
96
97 }