src/test/java/org/apache/james/mime4j/stream/RootInputStreamTest.java

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package org.apache.james.mime4j.stream;

import java.io.ByteArrayInputStream;
import java.io.IOException;

import org.apache.james.mime4j.stream.RootInputStream;


import junit.framework.TestCase;

public class RootInputStreamTest extends TestCase {

    public void testTruncate() throws IOException {
        String s = "Yada yada yada";
        RootInputStream is = 
            new RootInputStream(new ByteArrayInputStream(s.getBytes()));
        assertEquals(s.charAt(0), (char) is.read());
        assertEquals(s.charAt(1), (char) is.read());
        assertEquals(s.charAt(2), (char) is.read());
        assertEquals(s.charAt(3), (char) is.read());
        is.truncate();
        assertEquals(-1, is.read());
        byte[] buf = new byte[100];
        assertEquals(-1, is.read(buf));
        assertEquals(-1, is.read(buf, 2, 5));
    }

    /**
     * Tests that reading single bytes updates the line number appropriately.
     */
    public void testReadSingleByte() throws IOException {
        String s = "Yada\r\nyada\r\nyada\r\n";
        RootInputStream is = 
            new RootInputStream(new ByteArrayInputStream(s.getBytes()));
        
        for (int i = 0; i < 6; i++) {
            assertEquals(1, is.getLineNumber());
            is.read();
        }
        
        for (int i = 6; i < 12; i++) {
            assertEquals(2, is.getLineNumber());
            is.read();
        }
        
        for (int i = 12; i < 18; i++) {
            assertEquals(3, is.getLineNumber());
            is.read();
        }
        
        assertEquals(4, is.getLineNumber());
        assertEquals(-1, is.read());
    }
    
    /**
     * Tests that reading multiple bytes at once 
     * updates the line number appropriately.
     */
    public void testReadManyBytes() throws IOException {
        String s = "Yada\r\nyada\r\nyada\r\n";
        RootInputStream is = 
            new RootInputStream(new ByteArrayInputStream(s.getBytes()));
        
        byte[] buf = new byte[4];
        assertEquals(1, is.getLineNumber());
        is.read(buf);
        assertEquals(1, is.getLineNumber());
        is.read(buf);
        assertEquals(2, is.getLineNumber());
        is.read(buf);
        assertEquals(3, is.getLineNumber());
        is.read(buf);
        assertEquals(3, is.getLineNumber());
        is.read(buf);
        assertEquals(4, is.getLineNumber());
        
        assertEquals(-1, is.read());
    }
}