diff --git a/mute-idiom/pom.xml b/mute-idiom/pom.xml
new file mode 100644
index 000000000..e4597446b
--- /dev/null
+++ b/mute-idiom/pom.xml
@@ -0,0 +1,47 @@
+
+
+
+ 4.0.0
+
+ com.iluwatar
+ java-design-patterns
+ 1.11.0-SNAPSHOT
+
+ mute-idiom
+
+
+ junit
+ junit
+ test
+
+
+ org.mockito
+ mockito-core
+ test
+
+
+
diff --git a/mute-idiom/src/main/java/com/iluwatar/mute/App.java b/mute-idiom/src/main/java/com/iluwatar/mute/App.java
new file mode 100644
index 000000000..edb5ebcc9
--- /dev/null
+++ b/mute-idiom/src/main/java/com/iluwatar/mute/App.java
@@ -0,0 +1,77 @@
+/**
+ * The MIT License
+ * Copyright (c) 2014 Ilkka Seppälä
+ *
+ * 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 com.iluwatar.mute;
+
+import java.io.ByteArrayOutputStream;
+import java.sql.Connection;
+import java.sql.SQLException;
+
+public class App {
+
+ public static void main(String[] args) {
+
+ useOfLoggedMute();
+
+ useOfMute();
+ }
+
+ /*
+ * Typically used when the API declares some exception but cannot do so. Usually a signature mistake.
+ * In this example out is not supposed to throw exception as it is a ByteArrayOutputStream. So we
+ * utilize mute, which will throw AssertionError if unexpected exception occurs.
+ */
+ private static void useOfMute() {
+ ByteArrayOutputStream out = new ByteArrayOutputStream();
+ Mute.mute(() -> out.write("Hello".getBytes()));
+ }
+
+ private static void useOfLoggedMute() {
+ Connection connection = openConnection();
+ try {
+ readStuff(connection);
+ } catch (SQLException ex) {
+ ex.printStackTrace();
+ } finally {
+ closeConnection(connection);
+ }
+ }
+
+ /*
+ * All we can do while failed close of connection is to log it.
+ */
+ private static void closeConnection(Connection connection) {
+ if (connection != null) {
+ Mute.loggedMute(() -> connection.close());
+ }
+ }
+
+ private static void readStuff(Connection connection) throws SQLException {
+ if (connection != null) {
+ connection.createStatement();
+ }
+ }
+
+ private static Connection openConnection() {
+ return null;
+ }
+}
diff --git a/mute-idiom/src/main/java/com/iluwatar/mute/CheckedRunnable.java b/mute-idiom/src/main/java/com/iluwatar/mute/CheckedRunnable.java
new file mode 100644
index 000000000..7f99386f0
--- /dev/null
+++ b/mute-idiom/src/main/java/com/iluwatar/mute/CheckedRunnable.java
@@ -0,0 +1,36 @@
+/**
+ * The MIT License
+ * Copyright (c) 2014 Ilkka Seppälä
+ *
+ * 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 com.iluwatar.mute;
+
+/**
+ * A runnable which may throw exception on execution.
+ *
+ */
+@FunctionalInterface
+public interface CheckedRunnable {
+ /**
+ * Same as {@link Runnable#run()} with a possibility of exception in execution.
+ * @throws Exception if any exception occurs.
+ */
+ public void run() throws Exception;
+}
diff --git a/mute-idiom/src/main/java/com/iluwatar/mute/Mute.java b/mute-idiom/src/main/java/com/iluwatar/mute/Mute.java
new file mode 100644
index 000000000..ba055422b
--- /dev/null
+++ b/mute-idiom/src/main/java/com/iluwatar/mute/Mute.java
@@ -0,0 +1,65 @@
+/**
+ * The MIT License
+ * Copyright (c) 2014 Ilkka Seppälä
+ *
+ * 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 com.iluwatar.mute;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+/**
+ * A utility class that allows you to utilize mute idiom.
+ */
+public final class Mute {
+
+ /**
+ * Executes the runnable
and throws the exception occurred within a {@link AssertionError}.
+ * This method should be utilized to mute the operations that are guaranteed not to throw an exception.
+ * For instance {@link ByteArrayOutputStream#write(byte[])} declares in it's signature that it can throw
+ * an {@link IOException}, but in reality it cannot. This is because the bulk write method is not overridden
+ * in {@link ByteArrayOutputStream}.
+ *
+ * @param runnable a runnable that should never throw an exception on execution.
+ */
+ public static void mute(CheckedRunnable runnable) {
+ try {
+ runnable.run();
+ } catch (Exception e) {
+ throw new AssertionError(e);
+ }
+ }
+
+ /**
+ * Executes the runnable
and logs the exception occurred on {@link System#err}.
+ * This method should be utilized to mute the operations about which most you can do is log.
+ * For instance while closing a connection to database, all you can do is log the exception
+ * occurred.
+ *
+ * @param runnable a runnable that may throw an exception on execution.
+ */
+ public static void loggedMute(CheckedRunnable runnable) {
+ try {
+ runnable.run();
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ }
+}
diff --git a/mute-idiom/src/test/java/com/iluwatar/mute/AppTest.java b/mute-idiom/src/test/java/com/iluwatar/mute/AppTest.java
new file mode 100644
index 000000000..8079c6acb
--- /dev/null
+++ b/mute-idiom/src/test/java/com/iluwatar/mute/AppTest.java
@@ -0,0 +1,15 @@
+package com.iluwatar.mute;
+
+import org.junit.Test;
+
+/**
+ * Tests that Mute idiom example runs without errors.
+ *
+ */
+public class AppTest {
+
+ @Test
+ public void test() {
+ App.main(null);
+ }
+}
diff --git a/mute-idiom/src/test/java/com/iluwatar/mute/MuteTest.java b/mute-idiom/src/test/java/com/iluwatar/mute/MuteTest.java
new file mode 100644
index 000000000..b0016a331
--- /dev/null
+++ b/mute-idiom/src/test/java/com/iluwatar/mute/MuteTest.java
@@ -0,0 +1,62 @@
+/**
+ * The MIT License
+ * Copyright (c) 2014 Ilkka Seppälä
+ *
+ * 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 com.iluwatar.mute;
+
+import static org.junit.Assert.assertTrue;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.PrintStream;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+public class MuteTest {
+
+ private static final String MESSAGE = "should not occur";
+
+ @Rule public ExpectedException exception = ExpectedException.none();
+
+ @Test
+ public void muteShouldRethrowUnexpectedExceptionAsAssertionError() throws Exception {
+ exception.expect(AssertionError.class);
+ exception.expectMessage(MESSAGE);
+
+ Mute.mute(() -> methodThrowingException());
+ }
+
+ private void methodThrowingException() throws Exception {
+ throw new Exception(MESSAGE);
+ }
+
+ @Test
+ public void loggedMuteShouldLogExceptionTraceBeforeSwallowingIt() throws IOException {
+ ByteArrayOutputStream stream = new ByteArrayOutputStream();
+ System.setErr(new PrintStream(stream));
+
+ Mute.loggedMute(() -> methodThrowingException());
+
+ assertTrue(new String(stream.toByteArray()).contains(MESSAGE));
+ }
+}