Jonathan Lalou's blog

Archive for the ‘long tweets’ Category

Case

On building a Groovy project with Maven, I got the following error:

Error injecting: org.codehaus.groovy.eclipse.compiler.GroovyEclipseCompiler
java.lang.NoClassDefFoundError: org/codehaus/plexus/compiler/CompilerResult

Quick fix

Downgrade maven-compiler-plugin to version 3.0 instead of branch 2.3.X.

Run this command:

java com.sun.org.apache.xalan.internal.xslt.EnvironmentCheck

Case

How to make ChromeOS work in VirtualBox without Wifi, ie on an ethernet/wired local network, or even offline?

Quick Fix

Shutdown the VM > Select it > Settings > Network > Advanced > Adapter Type > select “Paravirtualized Network (virtio-net)”

Case

On booting ChromeOS Vanilla within Virtual Box, I got the following error:

This kernel requires the following features not present on the CPU: pae
Unable to boot - please use a kernel appropriate for your CPU.

(Actually, the problem occured with ChromeOS but may have appened with another system)

Quick Fix

In Virtual Box, select the VM > Settings > Processor > check “Enable PAE/NX”.

A short reminder: in a try/catch/finally section, the block in the finally is always executed. “Always” means “even if a return statement is reached in the try or catch“.

A short piece of code shows more than a long speech. The following JUnit test ends with no error:

package com.stepinfo.poc.cartography;

import org.junit.Test;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotSame;

/**
 * Created with IntelliJ IDEA 12 "Leda" CE
 * User: Jonathan LALOU
 * Date: 08/Apr/13
 * Time: 22:41
 */
public class TestTryCatchFinally {

    public static final String TRY = "try";
    public static final String CATCH = "catch";
    public static final String FINALLY = "finally";

    private String tryVersusFinally() {
        try {
            return TRY;
        } catch (Exception e) {
            return CATCH;
        } finally {
            return FINALLY;
        }
    }

    private String catchVersusFinally() {
        try {
            throw new RuntimeException();
        } catch (Exception e) {
            return CATCH;
        } finally {
            return FINALLY;
        }
    }

    @Test
    public void testTryFinally() {
        assertNotSame(TRY, tryVersusFinally());
        assertEquals(FINALLY, tryVersusFinally());
    }

    @Test
    public void testCatchFinally() {
        assertNotSame(CATCH, tryVersusFinally());
        assertEquals(FINALLY, catchVersusFinally());
    }
}