BAEL-1044 - Introduction to NoException (#2412)

* BAEL-1044 - Introduction to NoException

* BAEL-1044 - Introduction to NoException

* BAEL-1044 - Introduction to NoException

* BAEL-1044 - Introduction to NoException

* BAEL-1044 - Introduction to NoException

* Update pom.xml

Add missing </dependency>

libraries/README.md

@@ -29,6 +29,8 @@
 - [Introduction to Neuroph](http://www.baeldung.com/intro-to-neuroph)
 - [Guide to Apache Commons CircularFifoQueue](http://www.baeldung.com/commons-circular-fifo-queue)
 - [Quick Guide to RSS with Rome](http://www.baeldung.com/rome-rss)
+- [Introduction to NoException](http://www.baeldung.com/intrduction-to-noexception)
+
 
 The libraries module contains examples related to small libraries that are relatively easy to use and does not require any separate module of its own.
 

libraries/pom.xml

@@ -462,6 +462,11 @@
 			<artifactId>pcollections</artifactId>
 			<version>${pcollections.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>com.machinezoo.noexception</groupId>
+			<artifactId>noexception</artifactId>
+			<version>1.1.0</version>
+		</dependency>
     <dependency>
 			<groupId>org.eclipse.collections</groupId>
 			<artifactId>eclipse-collections</artifactId>
@@ -510,4 +515,4 @@
 		<rome.version>1.0</rome.version>
     <eclipse-collections.version>8.2.0</eclipse-collections.version>
 	</properties>
-</project>
+</project>

libraries/src/main/java/com/baeldung/noexception/CustomExceptionHandler.java

@@ -0,0 +1,24 @@
+package com.baeldung.noexception;
+
+import com.machinezoo.noexception.ExceptionHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class CustomExceptionHandler extends ExceptionHandler {
+
+    private Logger logger = LoggerFactory.getLogger(CustomExceptionHandler.class);
+
+    @Override
+    public boolean handle(Throwable throwable) {
+
+        if (throwable.getClass()
+            .isAssignableFrom(RuntimeException.class)
+            || throwable.getClass()
+                .isAssignableFrom(Error.class)) {
+            return false;
+        } else {
+            logger.error("Caught Exception ", throwable);
+            return true;
+        }
+    }
+}

libraries/src/test/java/com/baeldung/noexception/NoExceptionUnitTest.java

@@ -0,0 +1,62 @@
+package com.baeldung.noexception;
+
+import com.machinezoo.noexception.Exceptions;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class NoExceptionUnitTest {
+
+    private static Logger logger = LoggerFactory.getLogger(NoExceptionUnitTest.class);
+
+    @Test
+    public void whenStdExceptionHandling_thenCatchAndLog() {
+        try {
+            System.out.println("Result is " + Integer.parseInt("foobar"));
+        } catch (Throwable exception) {
+            logger.error("Caught exception:", exception);
+        }
+    }
+
+    @Test
+    public void whenDefaultNoException_thenCatchAndLog() {
+        Exceptions.log().run(() -> System.out.println("Result is " + Integer.parseInt("foobar")));
+    }
+
+    @Test
+    public void givenLogger_whenDefaultNoException_thenCatchAndLogWithClassName() {
+        Exceptions.log(logger).run(() -> System.out.println("Result is " + Integer.parseInt("foobar")));
+    }
+
+    @Test
+    public void givenLoggerAndMessage_whenDefaultNoException_thenCatchAndLogWithMessage() {
+        Exceptions.log(logger, "Something went wrong:").run(() -> System.out.println("Result is " + Integer.parseInt("foobar")));
+    }
+
+    @Test
+    public void givenDefaultValue_whenDefaultNoException_thenCatchAndLogPrintDefault() {
+        System.out.println("Result is " + Exceptions.log(logger, "Something went wrong:").get(() -> Integer.parseInt("foobar")).orElse(-1));
+    }
+
+    @Test(expected = Error.class)
+    public void givenCustomHandler_whenError_thenRethrowError() {
+        CustomExceptionHandler customExceptionHandler = new CustomExceptionHandler();
+        customExceptionHandler.run(() -> throwError());
+    }
+
+    @Test
+    public void givenCustomHandler_whenException_thenCatchAndLog() {
+        CustomExceptionHandler customExceptionHandler = new CustomExceptionHandler();
+        customExceptionHandler.run(() -> throwException());
+    }
+
+    private static void throwError() {
+        throw new Error("This is very bad.");
+    }
+
+    private static void throwException() {
+        String testString = "foo";
+        testString.charAt(5);
+    }
+
+}