slf4j-simple/src/test/java/org/slf4j/simple/DetectLoggerNameMismatchTest.java

/**
 * Copyright (c) 2004-2011 QOS.ch
 * All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining
 * a  copy  of this  software  and  associated  documentation files  (the
 * "Software"), to  deal in  the Software without  restriction, including
 * without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
 * permit persons to whom the Software  is furnished to do so, subject to
 * the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be
 * included in all copies or substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */
package org.slf4j.simple;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.slf4j.LoggerFactoryFriend;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

/**
 * Tests that detecting logger name mismatches works and doesn't cause problems
 * or trigger if disabled.
 * <p>
 * This test can't live inside slf4j-api because the NOP Logger doesn't
 * remember its name.
 *
 * @author Alexander Dorokhine
 * @author Ceki G&uuml;lc&uuml;
 */
public class DetectLoggerNameMismatchTest {

    private static final String MISMATCH_STRING = "Detected logger name mismatch";

    static String NAME_OF_THIS_CLASS = DetectLoggerNameMismatchTest.class.getName();

    private final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
    private final PrintStream oldErr = System.err;

    @Before
    public void setUp() {
        System.setErr(new PrintStream(byteArrayOutputStream));
    }

    @After
    public void tearDown() {
        setTrialEnabled(false);
        System.setErr(oldErr);
    }

    /*
     * Pass in the wrong class to the Logger with the check disabled, and make sure there are no errors.
     */
    @Test
    public void testNoTriggerWithoutProperty() {
        setTrialEnabled(false);
        Logger logger = LoggerFactory.getLogger(String.class);
        assertEquals("java.lang.String", logger.getName());
        assertMismatchDetected(false);
    }

    /*
     * Pass in the wrong class to the Logger with the check enabled, and make sure there ARE errors.
     */
    @Test
    public void testTriggerWithProperty() {
        setTrialEnabled(true);
        LoggerFactory.getLogger(String.class);
        assertMismatchDetected(true);
    }

    /*
     * Checks the whole error message to ensure all the names show up correctly.
     */
    @Test
    public void testTriggerWholeMessage() {
        setTrialEnabled(true);
        LoggerFactory.getLogger(String.class);
        boolean success = String.valueOf(byteArrayOutputStream)
                        .contains("Detected logger name mismatch. Given name: \"java.lang.String\"; " + "computed name: \"" + NAME_OF_THIS_CLASS + "\".");
        assertTrue("Actual value of byteArrayOutputStream: " + String.valueOf(byteArrayOutputStream), success);
    }

    /*
     * Checks that there are no errors with the check enabled if the class matches.
     */
    @Test
    public void testPassIfMatch() {
        setTrialEnabled(true);
        Logger logger = LoggerFactory.getLogger(DetectLoggerNameMismatchTest.class);
        assertEquals(DetectLoggerNameMismatchTest.class.getName(), logger.getName());
        assertMismatchDetected(false);
    }

    private void assertMismatchDetected(boolean mismatchDetected) {
        assertEquals(mismatchDetected, String.valueOf(byteArrayOutputStream).contains(MISMATCH_STRING));
    }

    @Test
    public void verifyLoggerDefinedInBaseWithOverridenGetClassMethod() {
        setTrialEnabled(true);
        Square square = new Square();
        assertEquals(Square.class.getName(), square.logger.getName());
        assertMismatchDetected(false);
    }

    private static void setTrialEnabled(boolean enabled) {
        // The system property is read into a static variable at initialization time
        // so we cannot just reset the system property to test this feature.
        // Therefore we set the variable directly.
        LoggerFactoryFriend.setDetectLoggerNameMismatch(enabled);
    }
}

// Used for testing that inheritance is ignored by the checker.
class ShapeBase {
    public Logger logger = LoggerFactory.getLogger(getClass());
}

class Square extends ShapeBase {
}