java stream exception hanling

Author: basahota

exception_handling/CheckedExceptionHandlerConsumer.java

@@ -0,0 +1,7 @@
+package com.javatechie.exception_handling;
+
+@FunctionalInterface
+public interface CheckedExceptionHandlerConsumer<Target,ExObj extends Exception> {
+
+    public void accept(Target target) throws ExObj;
+}

exception_handling/ExceptionHandlingExample.java

@@ -0,0 +1,74 @@
+package com.javatechie.exception_handling;
+
+import java.lang.annotation.Target;
+import java.util.*;
+import java.util.function.Consumer;
+import java.util.stream.Collectors;
+
+public class ExceptionHandlingExample {
+
+    public static void main(String[] args) {
+
+        List<String> list = Arrays.asList("44", "373", "xyz");
+        List<Integer> list1 = Arrays.asList(1,0);
+       // list1.forEach(handleGenericException(s-> System.out.println(10/s),ArithmeticException.class));
+
+       // list.forEach(handleGenericException(s -> System.out.println(Integer.parseInt(s)),NumberFormatException.class));
+
+        // List<Integer> intList = list.stream().map(Integer::parseInt).collect(Collectors.toList());
+        // System.out.println(intList);
+
+        //handle exception for checkedException
+        List<Integer> list2 = Arrays.asList(10,20);
+
+        list2.forEach(handleCheckedExceptionConsumer(i->{
+            Thread.sleep(i);
+            System.out.println(i);
+        }));
+    }
+    //approach -2
+
+    public static void printList(String s) {
+        try {
+            System.out.println(Integer.parseInt(s));
+        } catch (Exception ex) {
+            System.out.println("exception : " + ex.getMessage());
+        }
+    }
+
+    static Consumer<String> handleExceptionIfAny(Consumer<String> payload) {
+        return obj -> {
+            try {
+                payload.accept(obj);
+            } catch (Exception ex) {
+                System.out.println("exception : " + ex.getMessage());
+            }
+        };
+    }
+
+    static <Target, ExObj extends Exception> Consumer<Target> handleGenericException(Consumer<Target> targetConsumer,
+                                                                                     Class<ExObj> exObjClass) {
+        return obj -> {
+            try {
+                targetConsumer.accept(obj);
+            } catch (Exception ex) {
+                try {
+                    ExObj exObj = exObjClass.cast(ex);
+                    System.out.println("exception : " + exObj.getMessage());
+                } catch (ClassCastException ecx) {
+                    throw ex;
+                }
+            }
+        };
+    }
+
+    static  <Target> Consumer<Target> handleCheckedExceptionConsumer(CheckedExceptionHandlerConsumer<Target,Exception> handlerConsumer){
+        return obj -> {
+            try {
+                handlerConsumer.accept(obj);
+            } catch (Exception ex) {
+                throw new RuntimeException(ex);
+            }
+        };
+    }
+}