DoTryHandling.java

package eu.janbednar.stackoverflow.camelTest;

import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.RoutesBuilder;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.test.junit4.CamelTestSupport;
import org.junit.Assert;
import org.junit.Test;

public class DoTryHandling extends CamelTestSupport {

    class ThrowExceptionProcessor implements Processor {
        @Override
        public void process(Exchange exchange) throws Exception {
            if (exchange.getIn().getBody(String.class).equals("throw")){
                throw new IllegalStateException("Test exception");
            } else {
                exchange.getIn().setBody("Processed OK");
            }
        }
    }

    @Override
    protected RoutesBuilder createRouteBuilder() throws Exception {
        return new RouteBuilder() {
            @Override
            public void configure() throws Exception {
                from("direct:withProcessor")
                        .doTry()
                            .process(new ThrowExceptionProcessor())
                        .doCatch(Exception.class)
                            .process(new Processor() {
                                @Override
                                public void process(Exchange exchange) throws Exception {
                                    final Throwable ex = exchange.getProperty(Exchange.EXCEPTION_CAUGHT, Throwable.class);
                                    exchange.getIn().setBody(ex.getMessage());
                                }
                            })
                        .end();

                from("direct:withSimple")
                        .doTry()
                            .process(new ThrowExceptionProcessor())
                        .doCatch(Exception.class)
                            .transform().simple("${exception.message}")
                        .end();

                from("direct:withValueBuilder")
                        .doTry()
                            .process(new ThrowExceptionProcessor())
                        .doCatch(Exception.class)
                            .setBody(exceptionMessage())
                        .end();
            }
        };
    }

    @Test
    public void testProcessor() throws Exception{
        Assert.assertEquals("Test exception", template.requestBody("direct:withProcessor","throw"));
        Assert.assertEquals("Processed OK", template.requestBody("direct:withProcessor","do not throw"));
    }

    @Test
    public void testSimple() throws Exception{
        Assert.assertEquals("Test exception", template.requestBody("direct:withSimple","throw"));
        Assert.assertEquals("Processed OK", template.requestBody("direct:withSimple","do not throw"));
    }

    @Test
    public void testValueBuilder() throws Exception{
        Assert.assertEquals("Test exception", template.requestBody("direct:withValueBuilder","throw"));
        Assert.assertEquals("Processed OK", template.requestBody("direct:withValueBuilder","do not throw"));
    }
}