Add ExtractAppender to facilite junit tests

Added ExtractAppender to provide a way for junit tests to capture
data sent to a logger.
Changed logback.version to 1.2.3 and moved the property to the
top-level pom.
Updated license date in top-level pom.
Refactored ExceptionsText, adding ErrorsTester and
ThrowablesTester classes to reduce sonar issues.

Change-Id: Ief7d08972bf4e7037b59c2afe4b77b252f2ad60a
Issue-ID: POLICY-582
Signed-off-by: Jim Hahn <jrh3@att.com>

5 files changed, 858 insertions, 442 deletions

diff --git a/utils-test/src/main/java/org/onap/policy/common/utils/test/ConstructionError.java b/utils-test/src/main/java/org/onap/policy/common/utils/test/ConstructionError.java
new file mode 100644
index 00000000..336dc602
--- /dev/null
+++ b/utils-test/src/main/java/org/onap/policy/common/utils/test/ConstructionError.java
@@ -0,0 +1,58 @@
+/*
+ * ============LICENSE_START=======================================================
+ * Integrity Audit
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.test;
+
+/**
+ * An error that occurred while trying to construct an object for a junit test.
+ */
+public class ConstructionError extends AssertionError {
+	private static final long serialVersionUID = 1L;
+
+	/**
+	 * 
+	 */
+	public ConstructionError() {
+		super();
+	}
+
+	/**
+	 * @param message
+	 */
+	public ConstructionError(String message) {
+		super(message);
+	}
+
+	/**
+	 * @param cause
+	 */
+	public ConstructionError(Throwable cause) {
+		super(cause);
+	}
+
+	/**
+	 * @param message
+	 * @param cause
+	 */
+	public ConstructionError(String message, Throwable cause) {
+		super(message, cause);
+	}
+
+}
diff --git a/utils-test/src/main/java/org/onap/policy/common/utils/test/ErrorsTester.java b/utils-test/src/main/java/org/onap/policy/common/utils/test/ErrorsTester.java
new file mode 100644
index 00000000..12b48442
--- /dev/null
+++ b/utils-test/src/main/java/org/onap/policy/common/utils/test/ErrorsTester.java
@@ -0,0 +1,46 @@
+/*
+ * ============LICENSE_START=======================================================
+ * Integrity Monitor
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.test;
+
+/**
+ * Used to test various Error subclasses. Uses reflection to identify the
+ * constructors that the subclass supports.
+ */
+public class ErrorsTester extends ThrowablesTester {
+
+	/**
+	 * Runs tests, on an Error subclass, for all of the standard constructors.
+	 * If the Error subclass does not support a given type of constructor, then
+	 * it skips that test. Does <i>not</i> throw an exception if no standard
+	 * constructors are found.
+	 * 
+	 * @param claz
+	 *            subclass to be tested
+	 * @return the number of constructors that were found/tested
+	 * @throws ConstructionError
+	 *             if the Error subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Error> int testError(Class<T> claz) {
+		return testThrowable(claz);
+	}
+}
diff --git a/utils-test/src/main/java/org/onap/policy/common/utils/test/ExceptionsTester.java b/utils-test/src/main/java/org/onap/policy/common/utils/test/ExceptionsTester.java
index 8705c48c..156fca89 100644
--- a/utils-test/src/main/java/org/onap/policy/common/utils/test/ExceptionsTester.java
+++ b/utils-test/src/main/java/org/onap/policy/common/utils/test/ExceptionsTester.java
@@ -22,7 +22,6 @@ package org.onap.policy.common.utils.test;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 import java.lang.reflect.Constructor;
@@ -31,7 +30,7 @@ import java.lang.reflect.Constructor;
  * Used to test various Exception subclasses. Uses reflection to identify the
  * constructors that the subclass supports.
  */
-public class ExceptionsTester {
+public class ExceptionsTester extends ThrowablesTester {
 
 	/**
 	 * Runs tests, on an Exception subclass, for all of the standard
@@ -40,144 +39,43 @@ public class ExceptionsTester {
 	 * 
 	 * @param claz
 	 *            subclass to be tested
-	 * @return the number of constructors that the test found/tested
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
+	 * @return the number of constructors that were found/tested
+	 * @throws ConstructionError
+	 *             if the Exception subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
 	 */
-	public <T extends Exception> int test(Class<T> claz) throws Exception {
-		int ncons = 0;
+	public <T extends Exception> int test(Class<T> claz) {
+		int ncons = testException(claz);
 
-		ncons += testDefault(claz);
-		ncons += testString(claz);
-		ncons += testThrowable(claz);
-		ncons += testException(claz);
-		ncons += testStringThrowable(claz);
-		ncons += testStringException(claz);
-		ncons += testStringThrowableBooleanBoolean(claz);
-		ncons += testStringExceptionBooleanBoolean(claz);
-		
 		assertTrue(ncons > 0);
 
 		return ncons;
 	}
 
 	/**
-	 * Tests exceptions created via the default constructor. Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns null</li>
-	 * <li><i>getCause()</i> returns null</li>
-	 * </ul>
-	 * 
-	 * If the Exception subclass does not support this type of constructor, then
-	 * this method simply returns.
-	 * 
-	 * @param claz
-	 *            subclass to be tested
-	 * @return {@code 1}, if the subclass supports this type of constructor,
-	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> int testDefault(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor();
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
-			return 0;
-		}
-
-		T ex = cons.newInstance();
-
-		assertNotNull(ex.toString());
-		assertNull(ex.getMessage());
-		assertNull(ex.getCause());
-
-		return 1;
-	}
-
-	/**
-	 * Tests exceptions created via the constructor that takes just a String.
-	 * Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the original message passed to the
-	 * constructor</li>
-	 * <li><i>getCause()</i> returns null</li>
-	 * </ul>
-	 * 
-	 * If the Exception subclass does not support this type of constructor, then
-	 * this method simply returns.
-	 * 
-	 * @param claz
-	 *            subclass to be tested
-	 * @return {@code 1}, if the subclass supports this type of constructor,
-	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> int testString(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor(String.class);
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
-			return 0;
-		}
-
-		T ex = cons.newInstance("hello");
-
-		assertNotNull(ex.toString());
-		assertEquals("hello", ex.getMessage());
-		assertNull(ex.getCause());
-
-		return 1;
-	}
-
-	/**
-	 * Tests exceptions created via the constructor that takes just a Throwable.
-	 * Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the cause's message</li>
-	 * <li><i>getCause()</i> returns the original cause passed to the
-	 * constructor</li>
-	 * </ul>
-	 * 
-	 * If the Exception subclass does not support this type of constructor, then
-	 * this method simply returns.
+	 * Runs tests, on an Exception subclass, for all of the standard
+	 * constructors. If the Exception subclass does not support a given type of
+	 * constructor, then it skips that test. Does <i>not</i> throw an exception
+	 * if no standard constructors are found.
 	 * 
 	 * @param claz
 	 *            subclass to be tested
-	 * @return {@code 1}, if the subclass supports this type of constructor,
-	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
+	 * @return the number of constructors that were found/tested
+	 * @throws ConstructionError
+	 *             if the Exception subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
 	 */
-	public <T extends Exception> int testThrowable(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor(Throwable.class);
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
-			return 0;
-		}
-
-		Throwable cause = new Throwable("expected exception");
-		T ex = cons.newInstance(cause);
+	public <T extends Exception> int testException(Class<T> claz) {
+		int ncons = 0;
 
-		assertEquals(ex.getMessage(), ex.getMessage());
-		assertNotNull(ex.toString());
-		assertEquals(cause, ex.getCause());
+		ncons += testThrowable(claz);
+		ncons += testException_Exception(claz);
+		ncons += testException_StringException(claz);
+		ncons += testException_StringExceptionBooleanBoolean(claz);
 
-		return 1;
+		return ncons;
 	}
 
 	/**
@@ -197,22 +95,19 @@ public class ExceptionsTester {
 	 *            subclass to be tested
 	 * @return {@code 1}, if the subclass supports this type of constructor,
 	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
+	 * @throws ConstructionError
+	 *             if the Exception subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
 	 */
-	public <T extends Exception> int testException(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor(Exception.class);
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
+	public <T extends Exception> int testException_Exception(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "exception", Exception.class);
+		if (cons == null) {
 			return 0;
 		}
 
-		Exception cause = new Exception("expected exception");
-		T ex = cons.newInstance(cause);
+		Exception cause = new Exception(EXPECTED_EXCEPTION_MSG);
+		T ex = newInstance(cons, cause);
 
 		assertNotNull(ex.toString());
 		assertEquals(ex.getMessage(), ex.getMessage());
@@ -222,48 +117,6 @@ public class ExceptionsTester {
 	}
 
 	/**
-	 * Tests exceptions created via the constructor that takes a String and a
-	 * Throwable. Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the original message passed to the
-	 * constructor</li>
-	 * <li><i>getCause()</i> returns the original cause passed to the
-	 * constructor</li>
-	 * </ul>
-	 * 
-	 * If the Exception subclass does not support this type of constructor, then
-	 * this method simply returns.
-	 * 
-	 * @param claz
-	 *            subclass to be tested
-	 * @return {@code 1}, if the subclass supports this type of constructor,
-	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> int testStringThrowable(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor(String.class, Throwable.class);
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
-			return 0;
-		}
-
-		Throwable cause = new Throwable("expected exception");
-		T ex = cons.newInstance("world", cause);
-
-		assertNotNull(ex.toString());
-		assertEquals("world", ex.getMessage());
-		assertEquals(cause, ex.getCause());
-
-		return 1;
-	}
-
-	/**
 	 * Tests exceptions created via the constructor that takes a String and an
 	 * Exception. Verifies that:
 	 * <ul>
@@ -281,22 +134,17 @@ public class ExceptionsTester {
 	 *            subclass to be tested
 	 * @return {@code 1}, if the subclass supports this type of constructor,
 	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
+	 * @throws ConstructionError
+	 *             if the Exception subclass cannot be constructed
 	 */
-	public <T extends Exception> int testStringException(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor(String.class, Exception.class);
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
+	public <T extends Exception> int testException_StringException(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "string-exception", String.class, Exception.class);
+		if (cons == null) {
 			return 0;
 		}
 
-		Exception cause = new Exception("expected exception");
-		T ex = cons.newInstance("world", cause);
+		Exception cause = new Exception(EXPECTED_EXCEPTION_MSG);
+		T ex = newInstance(cons, "world", cause);
 
 		assertNotNull(ex.toString());
 		assertEquals("world", ex.getMessage());
@@ -306,52 +154,6 @@ public class ExceptionsTester {
 	}
 
 	/**
-	 * Tests exceptions created via the constructor that takes a String, a
-	 * Throwable, and two booleans. Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the original message passed to the
-	 * constructor</li>
-	 * <li><i>getCause()</i> returns the original cause passed to the
-	 * constructor</li>
-	 * <li>suppressed exceptions can be added, if enabled</li>
-	 * <li>the stack trace can be added, if enabled</li>
-	 * </ul>
-	 * 
-	 * If the Exception subclass does not support this type of constructor, then
-	 * this method simply returns.
-	 * 
-	 * @param claz
-	 *            subclass to be tested
-	 * @return {@code 1}, if the subclass supports this type of constructor,
-	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> int testStringThrowableBooleanBoolean(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor(String.class, Throwable.class, Boolean.TYPE, Boolean.TYPE);
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
-			return 0;
-		}
-
-		// test each combination of "message" and "cause"
-		testMessageCauseCombos(cons);
-
-		// test each combination of the boolean flags
-		testSuppressStack(cons);
-		testSuppressNoStack(cons);
-		testNoSuppressStack(cons);
-		testNoSuppressNoStack(cons);
-
-		return 1;
-	}
-
-	/**
 	 * Tests exceptions created via the constructor that takes a String, an
 	 * Exception, and two booleans. Verifies that:
 	 * <ul>
@@ -371,218 +173,22 @@ public class ExceptionsTester {
 	 *            subclass to be tested
 	 * @return {@code 1}, if the subclass supports this type of constructor,
 	 *         {@code 0} otherwise
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
+	 * @throws ConstructionError
+	 *             if the Exception subclass cannot be constructed
 	 */
-	public <T extends Exception> int testStringExceptionBooleanBoolean(Class<T> claz) throws Exception {
-		Constructor<T> cons;
-
-		try {
-			cons = claz.getConstructor(String.class, Exception.class, Boolean.TYPE, Boolean.TYPE);
-
-		} catch (NoSuchMethodException | SecurityException e) {
-			// this constructor is not defined so nothing to test
+	public <T extends Exception> int testException_StringExceptionBooleanBoolean(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "string-exception-flags", String.class, Exception.class,
+				Boolean.TYPE, Boolean.TYPE);
+		if (cons == null) {
 			return 0;
 		}
 
 		// test each combination of "message" and "cause"
-		testMessageCauseCombos(cons);
+		testThrowable_MessageCauseCombos(cons);
 
 		// test each combination of the boolean flags
-		testFlagCombos(cons);
+		testThrowable_FlagCombos(cons);
 
 		return 1;
 	}
-
-	/**
-	 * Tests each combination of values for the "message" and the "cause" when
-	 * using the constructor that takes a String, a Throwable/Exception, and two
-	 * booleans. Verifies that expected values are returned by <i>toString()/i>,
-	 * <i>getMessage()</i>, and <i>getCause()</i>.
-	 * </ul>
-	 * 
-	 * @param cons
-	 *            constructor to be invoked
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	private <T extends Exception> void testMessageCauseCombos(Constructor<T> cons) throws Exception {
-		T ex;
-		Exception cause = new Exception("expected throwable");
-
-		ex = cons.newInstance(null, null, true, true);
-		assertNotNull(ex.toString());
-		assertNull(ex.getMessage());
-		assertNull(ex.getCause());
-
-		ex = cons.newInstance("abc", null, true, true);
-		assertNotNull(ex.toString());
-		assertEquals("abc", ex.getMessage());
-		assertNull(ex.getCause());
-
-		ex = cons.newInstance(null, cause, true, true);
-		assertNotNull(ex.toString());
-		assertNull(ex.getMessage());
-		assertEquals(cause, ex.getCause());
-
-		ex = cons.newInstance("xyz", cause, true, true);
-		assertNotNull(ex.toString());
-		assertEquals("xyz", ex.getMessage());
-		assertEquals(cause, ex.getCause());
-	}
-
-	/**
-	 * Tests each combination of values for the "message" and the "cause" when
-	 * using the constructor that takes a String, a Throwable/Exception, and two
-	 * booleans. Verifies that expected values are returned by <i>toString()/i>,
-	 * <i>getMessage()</i>, and <i>getCause()</i>.
-	 * </ul>
-	 * 
-	 * @param cons
-	 *            constructor to be invoked
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> void testFlagCombos(Constructor<T> cons) throws Exception {
-		testSuppressStack(cons);
-		testSuppressNoStack(cons);
-		testNoSuppressStack(cons);
-		testNoSuppressNoStack(cons);
-	}
-
-	/**
-	 * Tests exceptions constructed with {@code enableSuppression=true} and
-	 * {@code writableStackTrace=true}. Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the original message passed to the
-	 * constructor</li>
-	 * <li><i>getCause()</i> returns the original cause passed to the
-	 * constructor</li>
-	 * <li>suppressed exceptions are added</li>
-	 * <li>the stack trace is added</li>
-	 * </ul>
-	 * 
-	 * @param cons
-	 *            the exception's class constructor
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> void testSuppressStack(Constructor<T> cons) throws Exception {
-		Exception cause = new Exception("expected exception");
-		Throwable supr = new Throwable("expected suppressed exception");
-		T ex = cons.newInstance("yes,yes", cause, true, true);
-
-		ex.addSuppressed(supr);
-
-		assertNotNull(ex.toString());
-		assertEquals("yes,yes", ex.getMessage());
-		assertEquals(cause, ex.getCause());
-
-		assertEquals(1, ex.getSuppressed().length);
-		assertEquals(supr, ex.getSuppressed()[0]);
-
-		assertTrue(ex.getStackTrace().length > 0);
-	}
-
-	/**
-	 * Tests exceptions constructed with {@code enableSuppression=true} and
-	 * {@code writableStackTrace=false}. Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the original message passed to the
-	 * constructor</li>
-	 * <li><i>getCause()</i> returns the original cause passed to the
-	 * constructor</li>
-	 * <li>suppressed exceptions are added</li>
-	 * <li>the stack trace is <i>not</i> added</li>
-	 * </ul>
-	 * 
-	 * @param cons
-	 *            the exception's class constructor
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> void testSuppressNoStack(Constructor<T> cons) throws Exception {
-		Exception cause = new Exception("expected exception");
-		Throwable supr = new Throwable("expected suppressed exception");
-		T ex = cons.newInstance("yes,no", cause, true, false);
-
-		ex.addSuppressed(supr);
-
-		assertNotNull(ex.toString());
-		assertEquals("yes,no", ex.getMessage());
-		assertEquals(cause, ex.getCause());
-
-		assertEquals(1, ex.getSuppressed().length);
-		assertEquals(supr, ex.getSuppressed()[0]);
-
-		assertEquals(0, ex.getStackTrace().length);
-	}
-
-	/**
-	 * Tests exceptions constructed with {@code enableSuppression=false} and
-	 * {@code writableStackTrace=true}. Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the original message passed to the
-	 * constructor</li>
-	 * <li><i>getCause()</i> returns the original cause passed to the
-	 * constructor</li>
-	 * <li>suppressed exceptions are <i>not</i> added</li>
-	 * <li>the stack trace is added</li>
-	 * </ul>
-	 * 
-	 * @param cons
-	 *            the exception's class constructor
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> void testNoSuppressStack(Constructor<T> cons) throws Exception {
-		Exception cause = new Exception("expected exception");
-		Throwable supr = new Throwable("expected suppressed exception");
-		T ex = cons.newInstance("no,yes", cause, false, true);
-
-		ex.addSuppressed(supr);
-
-		assertNotNull(ex.toString());
-		assertEquals("no,yes", ex.getMessage());
-		assertEquals(cause, ex.getCause());
-
-		assertEquals(0, ex.getSuppressed().length);
-
-		assertTrue(ex.getStackTrace().length > 0);
-	}
-
-	/**
-	 * Tests exceptions constructed with {@code enableSuppression=false} and
-	 * {@code writableStackTrace=false}. Verifies that:
-	 * <ul>
-	 * <li><i>toString()</i> returns a non-null value</li>
-	 * <li><i>getMessage()</i> returns the original message passed to the
-	 * constructor</li>
-	 * <li><i>getCause()</i> returns the original cause passed to the
-	 * constructor</li>
-	 * <li>suppressed exceptions are <i>not</i> added</li>
-	 * <li>the stack trace is <i>not</i> added</li>
-	 * 
-	 * @param cons
-	 *            the exception's class constructor
-	 * @throws Exception
-	 *             if the Exception cannot be constructed
-	 */
-	public <T extends Exception> void testNoSuppressNoStack(Constructor<T> cons) throws Exception {
-		Exception cause = new Exception("expected exception");
-		Throwable supr = new Throwable("expected suppressed exception");
-		T ex = cons.newInstance("no,no", cause, false, false);
-
-		ex.addSuppressed(supr);
-
-		assertNotNull(ex.toString());
-		assertEquals("no,no", ex.getMessage());
-		assertEquals(cause, ex.getCause());
-
-		assertEquals(0, ex.getSuppressed().length);
-		assertEquals(0, ex.getStackTrace().length);
-	}
 }
diff --git a/utils-test/src/main/java/org/onap/policy/common/utils/test/ThrowablesTester.java b/utils-test/src/main/java/org/onap/policy/common/utils/test/ThrowablesTester.java
new file mode 100644
index 00000000..bd8db4fc
--- /dev/null
+++ b/utils-test/src/main/java/org/onap/policy/common/utils/test/ThrowablesTester.java
@@ -0,0 +1,515 @@
+/*
+ * ============LICENSE_START=======================================================
+ * Integrity Monitor
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Used to test various Throwable subclasses. Uses reflection to identify the
+ * constructors that the subclass supports.
+ */
+public class ThrowablesTester {
+
+	private static Logger logger = LoggerFactory.getLogger(ThrowablesTester.class);
+
+	public static final String EXPECTED_EXCEPTION_MSG = "expected exception";
+	private static final String EXPECTED_SUPPRESSED_EXCEPTION_MSG = "expected suppressed exception";
+
+	/**
+	 * Passed as a "cause" to constructors.
+	 */
+	public static final Exception CAUSE = new Exception(EXPECTED_EXCEPTION_MSG);
+
+	/**
+	 * Passed to new objects via the <i>addSuppressed()</i> method..
+	 */
+	public static final Throwable SUPPRESSED = new Throwable(EXPECTED_SUPPRESSED_EXCEPTION_MSG);
+
+	/**
+	 * Runs tests, on an Throwable subclass, for all of the standard
+	 * constructors. If the Throwable subclass does not support a given type of
+	 * constructor, then it skips that test. Does <i>not</i> throw an exception
+	 * if no standard constructors are found.
+	 * 
+	 * @param claz
+	 *            subclass to be tested
+	 * @return the number of constructors that were found/tested
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> int testThrowable(Class<T> claz) {
+		int ncons = 0;
+
+		ncons += testThrowable_Default(claz);
+		ncons += testThrowable_StringConstuctor(claz);
+		ncons += testThrowable_Throwable(claz);
+		ncons += testThrowable_StringThrowable(claz);
+		ncons += testThrowable_StringThrowableBooleanBoolean(claz);
+
+		return ncons;
+	}
+
+	/**
+	 * Tests Throwable objects created via the default constructor. Verifies
+	 * that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns null</li>
+	 * <li><i>getCause()</i> returns null</li>
+	 * </ul>
+	 * 
+	 * If the Throwable subclass does not support this type of constructor, then
+	 * this method simply returns.
+	 * 
+	 * @param claz
+	 *            subclass to be tested
+	 * @return {@code 1}, if the subclass supports this type of constructor,
+	 *         {@code 0} otherwise
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> int testThrowable_Default(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "default");
+		if (cons == null) {
+			return 0;
+		}
+
+		T ex = newInstance(cons);
+
+		assertNotNull(ex.toString());
+		assertNull(ex.getMessage());
+		assertNull(ex.getCause());
+
+		return 1;
+	}
+
+	/**
+	 * Tests Throwable objects created via the constructor that takes just a
+	 * String. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the original message passed to the
+	 * constructor</li>
+	 * <li><i>getCause()</i> returns null</li>
+	 * </ul>
+	 * 
+	 * If the Throwable subclass does not support this type of constructor, then
+	 * this method simply returns.
+	 * 
+	 * @param claz
+	 *            subclass to be tested
+	 * @return {@code 1}, if the subclass supports this type of constructor,
+	 *         {@code 0} otherwise
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> int testThrowable_StringConstuctor(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "string", String.class);
+		if (cons == null) {
+			return 0;
+		}
+
+		T ex = newInstance(cons, "hello");
+
+		assertNotNull(ex.toString());
+		assertEquals("hello", ex.getMessage());
+		assertNull(ex.getCause());
+
+		return 1;
+	}
+
+	/**
+	 * Tests Throwable objects created via the constructor that takes just a
+	 * Throwable. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the cause's message</li>
+	 * <li><i>getCause()</i> returns the original cause passed to the
+	 * constructor</li>
+	 * </ul>
+	 * 
+	 * If the Throwable subclass does not support this type of constructor, then
+	 * this method simply returns.
+	 * 
+	 * @param claz
+	 *            subclass to be tested
+	 * @return {@code 1}, if the subclass supports this type of constructor,
+	 *         {@code 0} otherwise
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> int testThrowable_Throwable(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "throwable", Throwable.class);
+		if (cons == null) {
+			return 0;
+		}
+
+		T ex = newInstance(cons, CAUSE);
+
+		assertEquals(ex.getMessage(), ex.getMessage());
+		assertNotNull(ex.toString());
+		assertEquals(CAUSE, ex.getCause());
+
+		return 1;
+	}
+
+	/**
+	 * Tests Throwable objects created via the constructor that takes a String
+	 * and a Throwable. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the original message passed to the
+	 * constructor</li>
+	 * <li><i>getCause()</i> returns the original cause passed to the
+	 * constructor</li>
+	 * </ul>
+	 * 
+	 * If the Throwable subclass does not support this type of constructor, then
+	 * this method simply returns.
+	 * 
+	 * @param claz
+	 *            subclass to be tested
+	 * @return {@code 1}, if the subclass supports this type of constructor,
+	 *         {@code 0} otherwise
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> int testThrowable_StringThrowable(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "string-throwable", String.class, Throwable.class);
+		if (cons == null) {
+			return 0;
+		}
+
+		T ex = newInstance(cons, "world", CAUSE);
+
+		assertNotNull(ex.toString());
+		assertEquals("world", ex.getMessage());
+		assertEquals(CAUSE, ex.getCause());
+
+		return 1;
+	}
+
+	/**
+	 * Tests Throwable objects created via the constructor that takes a String,
+	 * a Throwable, and two booleans. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the original message passed to the
+	 * constructor</li>
+	 * <li><i>getCause()</i> returns the original cause passed to the
+	 * constructor</li>
+	 * <li>suppressed exceptions can be added, if enabled</li>
+	 * <li>the stack trace can be added, if enabled</li>
+	 * </ul>
+	 * 
+	 * If the Throwable subclass does not support this type of constructor, then
+	 * this method simply returns.
+	 * 
+	 * @param claz
+	 *            subclass to be tested
+	 * @return {@code 1}, if the subclass supports this type of constructor,
+	 *         {@code 0} otherwise
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> int testThrowable_StringThrowableBooleanBoolean(Class<T> claz) {
+		Constructor<T> cons = getConstructor(claz, "string-throwable-flags", String.class, Throwable.class,
+				Boolean.TYPE, Boolean.TYPE);
+		if (cons == null) {
+			return 0;
+		}
+
+		// test each combination of "message" and "cause"
+		testThrowable_MessageCauseCombos(cons);
+
+		// test each combination of the boolean flags
+		testThrowable_SuppressStack(cons);
+		testThrowable_SuppressNoStack(cons);
+		testThrowable_NoSuppressStack(cons);
+		testThrowable_NoSuppressNoStack(cons);
+
+		return 1;
+	}
+
+	/**
+	 * Tests each combination of values for the "message" and the "cause" when
+	 * using the constructor that takes a String, a Throwable/Exception, and two
+	 * booleans. Verifies that expected values are returned by <i>toString()/i>,
+	 * <i>getMessage()</i>, and <i>getCause()</i>.
+	 * </ul>
+	 * 
+	 * @param cons
+	 *            constructor to be invoked
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> void testThrowable_MessageCauseCombos(Constructor<T> cons) {
+		T ex;
+
+		ex = newInstance(cons, null, null, true, true);
+		assertNotNull(ex.toString());
+		assertNull(ex.getMessage());
+		assertNull(ex.getCause());
+
+		ex = newInstance(cons, "abc", null, true, true);
+		assertNotNull(ex.toString());
+		assertEquals("abc", ex.getMessage());
+		assertNull(ex.getCause());
+
+		ex = newInstance(cons, null, CAUSE, true, true);
+		assertNotNull(ex.toString());
+		assertNull(ex.getMessage());
+		assertEquals(CAUSE, ex.getCause());
+
+		ex = newInstance(cons, "xyz", CAUSE, true, true);
+		assertNotNull(ex.toString());
+		assertEquals("xyz", ex.getMessage());
+		assertEquals(CAUSE, ex.getCause());
+	}
+
+	/**
+	 * Tests each combination of values for the "message" and the "cause" when
+	 * using the constructor that takes a String, a Throwable/Exception, and two
+	 * booleans. Verifies that expected values are returned by <i>toString()/i>,
+	 * <i>getMessage()</i>, and <i>getCause()</i>.
+	 * </ul>
+	 * 
+	 * @param cons
+	 *            constructor to be invoked
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> void testThrowable_FlagCombos(Constructor<T> cons) {
+		testThrowable_SuppressStack(cons);
+		testThrowable_SuppressNoStack(cons);
+		testThrowable_NoSuppressStack(cons);
+		testThrowable_NoSuppressNoStack(cons);
+	}
+
+	/**
+	 * Tests Throwable objects constructed with {@code enableSuppression=true}
+	 * and {@code writableStackTrace=true}. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the original message passed to the
+	 * constructor</li>
+	 * <li><i>getCause()</i> returns the original cause passed to the
+	 * constructor</li>
+	 * <li>suppressed exceptions are added</li>
+	 * <li>the stack trace is added</li>
+	 * </ul>
+	 * 
+	 * @param cons
+	 *            the throwable's class constructor
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> void testThrowable_SuppressStack(Constructor<T> cons) {
+		T ex = newInstance(cons, "yes,yes", CAUSE, true, true);
+
+		ex.addSuppressed(SUPPRESSED);
+
+		assertNotNull(ex.toString());
+		assertEquals("yes,yes", ex.getMessage());
+		assertEquals(CAUSE, ex.getCause());
+
+		assertEquals(1, ex.getSuppressed().length);
+		assertEquals(SUPPRESSED, ex.getSuppressed()[0]);
+
+		assertTrue(ex.getStackTrace().length > 0);
+	}
+
+	/**
+	 * Tests Throwable objects constructed with {@code enableSuppression=true}
+	 * and {@code writableStackTrace=false}. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the original message passed to the
+	 * constructor</li>
+	 * <li><i>getCause()</i> returns the original cause passed to the
+	 * constructor</li>
+	 * <li>suppressed exceptions are added</li>
+	 * <li>the stack trace is <i>not</i> added</li>
+	 * </ul>
+	 * 
+	 * @param cons
+	 *            the throwable's class constructor
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> void testThrowable_SuppressNoStack(Constructor<T> cons) {
+		T ex = newInstance(cons, "yes,no", CAUSE, true, false);
+
+		ex.addSuppressed(SUPPRESSED);
+
+		assertNotNull(ex.toString());
+		assertEquals("yes,no", ex.getMessage());
+		assertEquals(CAUSE, ex.getCause());
+
+		assertEquals(1, ex.getSuppressed().length);
+		assertEquals(SUPPRESSED, ex.getSuppressed()[0]);
+
+		assertEquals(0, ex.getStackTrace().length);
+	}
+
+	/**
+	 * Tests Throwable objects constructed with {@code enableSuppression=false}
+	 * and {@code writableStackTrace=true}. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the original message passed to the
+	 * constructor</li>
+	 * <li><i>getCause()</i> returns the original cause passed to the
+	 * constructor</li>
+	 * <li>suppressed exceptions are <i>not</i> added</li>
+	 * <li>the stack trace is added</li>
+	 * </ul>
+	 * 
+	 * @param cons
+	 *            the throwable's class constructor
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> void testThrowable_NoSuppressStack(Constructor<T> cons) {
+		T ex = newInstance(cons, "no,yes", CAUSE, false, true);
+
+		ex.addSuppressed(SUPPRESSED);
+
+		assertNotNull(ex.toString());
+		assertEquals("no,yes", ex.getMessage());
+		assertEquals(CAUSE, ex.getCause());
+
+		assertEquals(0, ex.getSuppressed().length);
+
+		assertTrue(ex.getStackTrace().length > 0);
+	}
+
+	/**
+	 * Tests Throwable objects constructed with {@code enableSuppression=false}
+	 * and {@code writableStackTrace=false}. Verifies that:
+	 * <ul>
+	 * <li><i>toString()</i> returns a non-null value</li>
+	 * <li><i>getMessage()</i> returns the original message passed to the
+	 * constructor</li>
+	 * <li><i>getCause()</i> returns the original cause passed to the
+	 * constructor</li>
+	 * <li>suppressed exceptions are <i>not</i> added</li>
+	 * <li>the stack trace is <i>not</i> added</li>
+	 * 
+	 * @param cons
+	 *            the throwable's class constructor
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 * @throws AssertionError
+	 *             if the constructed objects fail to pass various tests
+	 */
+	public <T extends Throwable> void testThrowable_NoSuppressNoStack(Constructor<T> cons) {
+		T ex = newInstance(cons, "no,no", CAUSE, false, false);
+
+		ex.addSuppressed(SUPPRESSED);
+
+		assertNotNull(ex.toString());
+		assertEquals("no,no", ex.getMessage());
+		assertEquals(CAUSE, ex.getCause());
+
+		assertEquals(0, ex.getSuppressed().length);
+		assertEquals(0, ex.getStackTrace().length);
+	}
+
+	/**
+	 * Attempts to get a constructor for objects of a given type.
+	 * 
+	 * @param claz
+	 *            class of objects whose constructor is to be gotten
+	 * @param testType
+	 *            type of test being run
+	 * @param argTypes
+	 *            argument types to be passed to the constructor
+	 * @return the desired constructor, or {@code null} if the desired
+	 *         constructor is not available
+	 */
+	protected <T extends Throwable> Constructor<T> getConstructor(Class<T> claz, String testType,
+			Class<?>... argTypes) {
+
+		try {
+			return claz.getConstructor(argTypes);
+
+		} catch (NoSuchMethodException | SecurityException e) {
+			// this constructor is not defined so nothing to test
+			logger.debug("skipped test due to no " + testType + " constructor for: " + claz);
+			return null;
+		}
+	}
+
+	/**
+	 * Creates a new instance of an Throwable subclass.
+	 * 
+	 * @param cons
+	 *            subclass constructor
+	 * @param args
+	 *            arguments to be passed to the constructor
+	 * @return a new instance of the Throwable subclass
+	 * @throws ConstructionError
+	 *             if the Throwable subclass cannot be constructed
+	 */
+	protected <T extends Throwable> T newInstance(Constructor<T> cons, Object... args) {
+		try {
+			return cons.newInstance(args);
+
+		} catch (InstantiationException | IllegalAccessException | IllegalArgumentException
+				| InvocationTargetException e) {
+
+			throw new ConstructionError(e);
+		}
+
+	}
+}
diff --git a/utils-test/src/main/java/org/onap/policy/common/utils/test/log/logback/ExtractAppender.java b/utils-test/src/main/java/org/onap/policy/common/utils/test/log/logback/ExtractAppender.java
new file mode 100644
index 00000000..f012464c
--- /dev/null
+++ b/utils-test/src/main/java/org/onap/policy/common/utils/test/log/logback/ExtractAppender.java
@@ -0,0 +1,191 @@
+/*
+ * ============LICENSE_START=======================================================
+ * Integrity Audit
+ * ================================================================================
+ * Copyright (C) 2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.test.log.logback;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Queue;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import ch.qos.logback.core.AppenderBase;
+
+/**
+ * This is an appender that is intended for use by JUnit tests that wish to
+ * capture logged messages. The appender takes an optional list of regular
+ * expressions that are used to identify and extract data of interest.
+ * <p/>
+ * If no patterns are provided, then every logged message is recorded. However,
+ * if patterns are provided, then only messages that match one of the patterns
+ * are recorded. In addition, if the pattern contains a capture group that is
+ * non-null, only the captured group is recorded. Otherwise, the entire portion
+ * of the message that matches the pattern is recorded.
+ * <p/>
+ * All operations are thread-safe.
+ */
+public class ExtractAppender extends AppenderBase<ILoggingEvent> {
+
+	/**
+	 * Extracted text is placed here.
+	 */
+	private final Queue<String> extracted;
+
+	/**
+	 * Regular expressions/Patterns to be used to extract text. Uses a
+	 * LinkedHashMap so that order is preserved.
+	 */
+	private final LinkedHashMap<String, Pattern> patterns;
+
+	/**
+	 * Records every message that is logged.
+	 */
+	public ExtractAppender() {
+		this(new LinkedList<>());
+	}
+
+	/**
+	 * Records portions of messages that match one of the regular expressions.
+	 * 
+	 * @param regex
+	 *            regular expression (i.e., {@link Pattern}) to match
+	 */
+	public ExtractAppender(String... regex) {
+		this(new LinkedList<>(), regex);
+	}
+
+	/**
+	 * Rather than allocating an internal queue to store matched messages,
+	 * messages are recorded in the specified target queue using the
+	 * {@link Queue#offer(Object)} method. Note: whenever the queue is used, it
+	 * will be synchronized to prevent simultaneous accesses.
+	 * 
+	 * @param target
+	 * @param regex
+	 *            regular expression (i.e., {@link Pattern}) to match
+	 */
+	public ExtractAppender(Queue<String> target, String... regex) {
+		extracted = target;
+		patterns = new LinkedHashMap<>(regex.length);
+
+		for (String re : regex) {
+			patterns.put(re, Pattern.compile(re));
+		}
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see ch.qos.logback.core.AppenderBase#append(Object)
+	 */
+	@Override
+	protected void append(ILoggingEvent event) {
+
+		String msg = event.getMessage();
+
+		synchronized (patterns) {
+			if (patterns.isEmpty()) {
+				addExtraction(msg);
+				return;
+			}
+
+			for (Pattern p : patterns.values()) {
+				Matcher m = p.matcher(msg);
+
+				if (m.find()) {
+					addGroupMatch(m);
+					break;
+				}
+			}
+		}
+	}
+
+	/**
+	 * Adds the first match group to {@link #extracted}.
+	 * 
+	 * @param mat
+	 *            the matcher containing the groups
+	 * @return {@code true} if a group was found, {@code false} otherwise
+	 */
+	private void addGroupMatch(Matcher mat) {
+		int ngroups = mat.groupCount();
+
+		for (int x = 1; x <= ngroups; ++x) {
+			String txt = mat.group(x);
+
+			if (txt != null) {
+				addExtraction(txt);
+				return;
+			}
+		}
+
+		addExtraction(mat.group());
+	}
+
+	/**
+	 * Adds an item to {@link #extracted}, in a thread-safe manner. It uses the
+	 * queue's <i>offer()</i> method so that the queue can discard the item if
+	 * it so chooses, without generating an exception.
+	 * 
+	 * @param txt
+	 *            text to be added
+	 */
+	private void addExtraction(String txt) {
+		synchronized (extracted) {
+			extracted.offer(txt);
+		}
+	}
+
+	/**
+	 * Gets the text that has been extracted.
+	 * 
+	 * @return a copy of the text that has been extracted
+	 */
+	public List<String> getExtracted() {
+		synchronized (extracted) {
+			return new ArrayList<>(extracted);
+		}
+	}
+
+	/**
+	 * Clears the list of extracted text.
+	 */
+	public void clearExtractions() {
+		synchronized (extracted) {
+			extracted.clear();
+		}
+	}
+
+	/**
+	 * Adds a pattern to be matched by this appender.
+	 * 
+	 * @param regex
+	 *            regular expression (i.e., {@link Pattern}) to match
+	 */
+	public void setPattern(String regex) {
+		synchronized (patterns) {
+			patterns.put(regex, Pattern.compile(regex));
+		}
+	}
+
+}