mockobjects-java-dev

[Steve F. <sm...@us...>]

Update of /cvsroot/mockobjects/mockobjects-java/src/jdk/common/com/mockobjects/io
In directory usw-pr-cvs1:/tmp/cvs-serv17107/src/jdk/common/com/mockobjects/io

Added Files:
	MockWriter.java 
Log Message:
new class 

--- NEW FILE: MockWriter.java ---
package com.mockobjects.io;

import com.mockobjects.ExpectationCounter;
import com.mockobjects.ExpectationSegment;
import com.mockobjects.Verifiable;
import com.mockobjects.util.Verifier;

import java.io.IOException;
import java.io.Writer;

/**
  * A mock {@link java.io.Writer Writer}.
  * <h3>Example usage</h3>
  * <p>
  * You may use the <code>MockWriter</code> like this:
  * <pre>
  * public void testSomething() throws IOException {
  *     MockWriter out = new MockWriter();
  *     out.setExpectedSegment("some string");
  *     out.setExpectedFlushCalls(1);
  *     out.setExpectedCloseCalls(1);
  *
  *     ObjectUnderTest testee = new ObjectUnderTest(out);
  *     out.verify();
  *
  *     // If we get here, the mock's flush() and close() methods were
  *     // called exactly once each (order cannot be determined) and
  *     // the write() method was called with the string "some string" in it.
  * }</pre>
  * </p>
  * @author Francois Beausoleil, fb...@us...
  */
public class MockWriter extends Writer implements Verifiable {
	private ExpectationSegment mySegment = new ExpectationSegment("String segment");
	private ExpectationCounter myFlushCalls = new ExpectationCounter("flush calls");
	private ExpectationCounter myCloseCalls = new ExpectationCounter("close calls");

	private boolean writeShouldThrowException = false;

	/**
	 * Instantiates a new mock writer which will act as a data sink.
	 * Once instantiated, mocks of this class do not expect anything  special.
	 * Once the object is instantiated, you should set your expectations using
	 * the provided methods.
	 */
	public MockWriter() {
	}

	/**
	 * Sets the mocks behavior when writing.
	 * When the {@link #write(char[],int,int) write(char[], int, int)} method
	 * is called, if this method was called with <code>true</code>, the mock
	 * will throw an {@link java.io.IOException IOException} instead of
	 * asserting a string segment.
	 * @param state Set to <code>true</code> if you want the mock to throw an
	 * exception, <code>false</code> otherwise.
	 */
	public void setWriteShouldThrowException(boolean state) {
		writeShouldThrowException = state;
	}

	/**
	 * Sets the expected number of times that the {@link #flush() flush()}
	 * method will be called.
	 * @see #flush()
	 */
	public void setExpectedFlushCalls(int calls) {
		myFlushCalls.setExpected(calls);
	}

	/**
	 * Sets the expected number of times that the {@link #close() close()}
	 * method will be called.
	 * @see #close()
	 */
	public void setExpectedCloseCalls(int calls) {
		myCloseCalls.setExpected(calls);
	}

	/**
	 * Sets the value of the expected string segment.
	 * When the {@link #write(char[], int, int) write(char[], int, int)} method
	 * is called, a string is instantiated with the passed array and compared
	 * to the <code>aString</code> parameter of this method.  If the two strings
	 * differ, an {@link junit.framework.AssertionFailedError} will be thrown.
	 * @see com.mockobjects.ExpectationSegment
	 * @see #write(char[], int, int)
	 */
	public void setExpectedSegment(String aString) {
		mySegment.setExpected(aString);
	}

	/**
	 * Either throws an exception or asserts a string segment for equality.
	 * @see com.mockobjects.ExpectationSegment
	 * @see #setWriteShouldThrowException(boolean)
	 */
	public void write(char cbuf[], int off, int len) throws IOException {
		if (writeShouldThrowException) {
			throw new IOException("Exception, as requested");
		}

		mySegment.setActual(new String(cbuf, off, len));
	}

	/**
	 * Increments the flush counter and asserts that this method was not
	 * called too many times.
	 * @see #setExpectedFlushCalls(int)
	 */
	public void flush() throws IOException {
		myFlushCalls.inc();
	}

	/**
	 * Increments the close counter and asserts that this method was not
	 * called too many times.
	 * @see #setExpectedCloseCalls(int)
	 */
	public void close() {
		myCloseCalls.inc();
	}

	public void verify() {
		mySegment.verify();
		myFlushCalls.verify();
		myCloseCalls.verify();
	}
}