Home | History | Annotate | Download | only in io 
      1 /*
      2  * Copyright (C) 2008 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 com.google.common.collect.ImmutableList;
     20 
     21 import junit.framework.TestCase;
     22 
     23 import java.io.FilterReader;
     24 import java.io.IOException;
     25 import java.io.Reader;
     26 import java.io.StringReader;
     27 
     28 /**
     29  * @author ricebin
     30  */
     31 public class MultiReaderTest extends TestCase {
     32 
     33   public void testOnlyOneOpen() throws Exception {
     34     String testString = "abcdefgh";
     35     final InputSupplier<Reader> supplier = newReader(testString);
     36     final int[] counter = new int[1];
     37     InputSupplier<Reader> reader = new InputSupplier<Reader>() {
     38       @Override
     39       public Reader getInput() throws IOException {
     40         if (counter[0]++ != 0) {
     41           throw new IllegalStateException("More than one supplier open");
     42         }
     43         return new FilterReader(supplier.getInput()) {
     44           @Override public void close() throws IOException {
     45             super.close();
     46             counter[0]--;
     47           }
     48         };
     49       }
     50     };
     51     @SuppressWarnings("unchecked")
     52     Reader joinedReader = CharStreams.join(reader, reader, reader).getInput();
     53     String result = CharStreams.toString(joinedReader);
     54     assertEquals(testString.length() * 3, result.length());
     55   }
     56 
     57   public void testReady() throws Exception {
     58     InputSupplier<Reader> supplier = newReader("a");
     59     Iterable<? extends InputSupplier<? extends Reader>> list = ImmutableList.of(supplier, supplier);
     60     Reader joinedReader = CharStreams.join(list).getInput();
     61 
     62     assertTrue(joinedReader.ready());
     63     assertEquals('a', joinedReader.read());
     64     assertEquals('a', joinedReader.read());
     65     assertEquals(-1, joinedReader.read());
     66     assertFalse(joinedReader.ready());
     67   }
     68 
     69   public void testSimple() throws Exception {
     70     String testString = "abcdefgh";
     71     InputSupplier<Reader> supplier = newReader(testString);
     72     @SuppressWarnings("unchecked")
     73     Reader joinedReader = CharStreams.join(supplier, supplier).getInput();
     74 
     75     String expectedString = testString + testString;
     76     assertEquals(expectedString, CharStreams.toString(joinedReader));
     77   }
     78 
     79 
     80   private static InputSupplier<Reader> newReader(final String text) {
     81     return new InputSupplier<Reader>() {
     82       @Override
     83       public Reader getInput() {
     84         return new StringReader(text);
     85       }
     86     };
     87   }
     88 
     89   public void testSkip() throws Exception {
     90     String begin = "abcde";
     91     String end = "fghij";
     92     @SuppressWarnings("unchecked")
     93     Reader joinedReader =
     94         CharStreams.join(newReader(begin), newReader(end)).getInput();
     95 
     96     String expected = begin + end;
     97     assertEquals(expected.charAt(0), joinedReader.read());
     98     CharStreams.skipFully(joinedReader, 1);
     99     assertEquals(expected.charAt(2), joinedReader.read());
    100     CharStreams.skipFully(joinedReader, 4);
    101     assertEquals(expected.charAt(7), joinedReader.read());
    102     CharStreams.skipFully(joinedReader, 1);
    103     assertEquals(expected.charAt(9), joinedReader.read());
    104     assertEquals(-1, joinedReader.read());
    105   }
    106 
    107   public void testSkipZero() throws Exception {
    108     InputSupplier<Reader> supplier = newReader("a");
    109     Iterable<? extends InputSupplier<? extends Reader>> list = ImmutableList.of(supplier, supplier);
    110     Reader joinedReader = CharStreams.join(list).getInput();
    111 
    112     assertEquals(0, joinedReader.skip(0));
    113     assertEquals('a', joinedReader.read());
    114   }
    115 
    116 }
    117