1 /* 2 * Copyright (C) 2007 The Guava Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.common.io; 18 19 import java.io.ByteArrayInputStream; 20 import java.io.IOException; 21 import java.io.InputStream; 22 23 /** 24 * @author Charles Fry 25 */ 26 public class LimitInputStreamTest extends IoTestCase { 27 testLimit()28 public void testLimit() throws Exception { 29 byte[] big = newPreFilledByteArray(5); 30 InputStream bin = new ByteArrayInputStream(big); 31 InputStream lin = new LimitInputStream(bin, 2); 32 33 // also test available 34 lin.mark(2); 35 assertEquals(2, lin.available()); 36 int read = lin.read(); 37 assertEquals(big[0], read); 38 assertEquals(1, lin.available()); 39 read = lin.read(); 40 assertEquals(big[1], read); 41 assertEquals(0, lin.available()); 42 read = lin.read(); 43 assertEquals(-1, read); 44 45 lin.reset(); 46 byte[] small = new byte[5]; 47 read = lin.read(small); 48 assertEquals(2, read); 49 assertEquals(big[0], small[0]); 50 assertEquals(big[1], small[1]); 51 52 lin.reset(); 53 read = lin.read(small, 2, 3); 54 assertEquals(2, read); 55 assertEquals(big[0], small[2]); 56 assertEquals(big[1], small[3]); 57 } 58 testMark()59 public void testMark() throws Exception { 60 byte[] big = newPreFilledByteArray(5); 61 InputStream bin = new ByteArrayInputStream(big); 62 InputStream lin = new LimitInputStream(bin, 2); 63 64 int read = lin.read(); 65 assertEquals(big[0], read); 66 lin.mark(2); 67 68 read = lin.read(); 69 assertEquals(big[1], read); 70 read = lin.read(); 71 assertEquals(-1, read); 72 73 lin.reset(); 74 read = lin.read(); 75 assertEquals(big[1], read); 76 read = lin.read(); 77 assertEquals(-1, read); 78 } 79 testSkip()80 public void testSkip() throws Exception { 81 byte[] big = newPreFilledByteArray(5); 82 InputStream bin = new ByteArrayInputStream(big); 83 InputStream lin = new LimitInputStream(bin, 2); 84 85 // also test available 86 lin.mark(2); 87 assertEquals(2, lin.available()); 88 lin.skip(1); 89 assertEquals(1, lin.available()); 90 91 lin.reset(); 92 assertEquals(2, lin.available()); 93 lin.skip(3); 94 assertEquals(0, lin.available()); 95 } 96 97 testMarkNotSet()98 public void testMarkNotSet() { 99 byte[] big = newPreFilledByteArray(5); 100 InputStream bin = new ByteArrayInputStream(big); 101 InputStream lin = new LimitInputStream(bin, 2); 102 103 try { 104 lin.reset(); 105 fail(); 106 } catch (IOException expected) { 107 assertEquals("Mark not set", expected.getMessage()); 108 } 109 } 110 testMarkNotSupported()111 public void testMarkNotSupported() { 112 InputStream lin = new LimitInputStream(new UnmarkableInputStream(), 2); 113 114 try { 115 lin.reset(); 116 fail(); 117 } catch (IOException expected) { 118 assertEquals("Mark not supported", expected.getMessage()); 119 } 120 } 121 122 private static class UnmarkableInputStream extends InputStream { 123 @Override read()124 public int read() throws IOException { 125 return 0; 126 } 127 128 @Override markSupported()129 public boolean markSupported() { 130 return false; 131 } 132 } 133 } 134