// exceptions/TurnOffChecking.java // (c)2021 MindView LLC: see Copyright.txt // We make no guarantees that this code is fit for any purpose. // Visit http://OnJava8.com for more book information. // "Turning off" Checked exceptions import java.io.*; class WrapCheckedException { void throwRuntimeException(int type) { try { switch(type) { case 0: throw new FileNotFoundException(); case 1: throw new IOException(); case 2: throw new RuntimeException("Where am I?"); default: return; } } catch(IOException | RuntimeException e) { // Adapt to unchecked: throw new RuntimeException(e); } } } class SomeOtherException extends Exception {} public class TurnOffChecking { public static void main(String[] args) { WrapCheckedException wce = new WrapCheckedException(); // You can call throwRuntimeException() without // a try block, and let RuntimeExceptions // leave the method: wce.throwRuntimeException(3); // Or you can choose to catch exceptions: for(int i = 0; i < 4; i++) try { if(i < 3) wce.throwRuntimeException(i); else throw new SomeOtherException(); } catch(SomeOtherException e) { System.out.println( "SomeOtherException: " + e); } catch(RuntimeException re) { try { throw re.getCause(); } catch(FileNotFoundException e) { System.out.println( "FileNotFoundException: " + e); } catch(IOException e) { System.out.println("IOException: " + e); } catch(Throwable e) { System.out.println("Throwable: " + e); } } } } /* Output: FileNotFoundException: java.io.FileNotFoundException IOException: java.io.IOException Throwable: java.lang.RuntimeException: Where am I? SomeOtherException: SomeOtherException */