Home | History | Annotate | Download | only in io 
      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.Closeable;
     20 import java.io.Flushable;
     21 import java.io.IOException;
     22 import java.io.Writer;
     23 
     24 /**
     25  * Unit test for {@link AppendableWriter}.
     26  *
     27  * @author Alan Green
     28  */
     29 public class AppendableWriterTest extends IoTestCase {
     30 
     31   /** Helper class for testing behavior with Flushable and Closeable targets. */
     32   private static class SpyAppendable implements Appendable, Flushable, Closeable {
     33     boolean flushed;
     34     boolean closed;
     35     StringBuilder result = new StringBuilder();
     36 
     37     @Override public Appendable append(CharSequence csq) {
     38       result.append(csq);
     39       return this;
     40     }
     41 
     42     @Override public Appendable append(char c) {
     43       result.append(c);
     44       return this;
     45     }
     46 
     47     @Override public Appendable append(CharSequence csq, int start, int end) {
     48       result.append(csq, start, end);
     49       return this;
     50     }
     51 
     52     @Override public void flush() {
     53       flushed = true;
     54     }
     55 
     56     @Override public void close() {
     57       closed = true;
     58     }
     59   }
     60 
     61   public void testWriteMethods() throws IOException {
     62     StringBuilder builder = new StringBuilder();
     63     Writer writer = new AppendableWriter(builder);
     64 
     65     writer.write("Hello".toCharArray());
     66     writer.write(',');
     67     writer.write(0xBEEF0020); // only lower 16 bits are important
     68     writer.write("Wo");
     69     writer.write("Whirled".toCharArray(), 3, 2);
     70     writer.write("Mad! Mad, I say", 2, 2);
     71 
     72     assertEquals("Hello, World!", builder.toString());
     73   }
     74 
     75   public void testAppendMethods() throws IOException {
     76     StringBuilder builder = new StringBuilder();
     77     Writer writer = new AppendableWriter(builder);
     78 
     79     writer.append("Hello,");
     80     writer.append(' ');
     81     writer.append("The World Wide Web", 4, 9);
     82     writer.append("!");
     83 
     84     assertEquals("Hello, World!", builder.toString());
     85   }
     86 
     87   public void testCloseFlush() throws IOException {
     88     SpyAppendable spy = new SpyAppendable();
     89     Writer writer = new AppendableWriter(spy);
     90 
     91     writer.write("Hello");
     92     assertFalse(spy.flushed);
     93     assertFalse(spy.closed);
     94 
     95     writer.flush();
     96     assertTrue(spy.flushed);
     97     assertFalse(spy.closed);
     98 
     99     writer.close();
    100     assertTrue(spy.flushed);
    101     assertTrue(spy.closed);
    102   }
    103 
    104   public void testCloseIsFinal() throws IOException {
    105     StringBuilder builder = new StringBuilder();
    106     Writer writer = new AppendableWriter(builder);
    107 
    108     writer.write("Hi");
    109     writer.close();
    110 
    111     try {
    112       writer.write(" Greg");
    113       fail("Should have thrown IOException due to writer already closed");
    114     } catch (IOException es) {
    115       // expected
    116     }
    117 
    118     try {
    119       writer.flush();
    120       fail("Should have thrown IOException due to writer already closed");
    121     } catch (IOException es) {
    122       // expected
    123     }
    124 
    125     // close()ing already closed writer is allowed
    126     writer.close();
    127   }
    128 }
    129