AutocloseableDemo

AutocloseableDemo.java

package com.gueck.dogdash;

public class AutocloseableDemo {

    private static class CreateException extends RuntimeException {}

    private static class CloseException extends RuntimeException {}

    private static class OperationException extends RuntimeException {}

    private static abstract class BasicOperable {
        public void operate() throws OperationException {}
    }

    private static class Create extends BasicOperable implements AutoCloseable {
        public Create() throws CreateException {
            System.err.println("create: calling create");
            throw new CreateException();
        }
        @Override
        public void close() throws CreateException {
            System.err.println("create: calling close");
        }
    }

    private static class Close extends BasicOperable implements AutoCloseable {
        public Close() {
            System.err.println("close: calling create");
        }
        @Override
        public void close() throws CloseException {
            System.err.println("close: calling close");
            throw new CloseException();
        }
    }

    private static class Operate extends BasicOperable implements AutoCloseable {
        public Operate() {
            System.err.println("operate: calling create");
        }
        @Override
        public void close() throws CloseException {
            System.err.println("operate: calling close");
        }
        @Override
        public void operate() throws OperationException {
            System.err.println("operate: calling operate");
            throw new OperationException();
        }
    }

    public static void main(final String ... args) {

        try(final Create create = new Create()) {
            create.operate();
        } catch (final CreateException e) {
            System.err.println("create: create exception");
        } catch (final OperationException e) {
            System.err.println("create: operation exception");
        } catch (final CloseException e) {
            System.err.println("create: close exception");
        }

        try(final Close close = new Close()) {
            close.operate();
        } catch (final CreateException e) {
            System.err.println("close: create exception");
        } catch (final OperationException e) {
            System.err.println("close: operation exception");
        } catch (final CloseException e) {
            System.err.println("close: close exception");
        }

        try(final Operate operate = new Operate()) {
            operate.operate();
        } catch (final CreateException e) {
            System.err.println("operate: create exception");
        } catch (final OperationException e) {
            System.err.println("operate: operation exception");
        } catch (final CloseException e) {
            System.err.println("operate: close exception");
        }

    }

}