Yes, from [http://maven.apache.org/plugin-developers/index.html][1]:

*What is a Mojo? A mojo is a Maven plain Old Java Object. Each mojo is an executable goal in Maven, and a plugin is a distribution of one or more related mojos.*

In short, a mojo is a maven goal, to extend functionality not already found in maven.

  [1]: http://maven.apache.org/plugin-developers/index.html

As written [here](http://books.sonatype.com/mvnref-book/reference/writing-plugins-sect-programming-maven.html):

&gt; A Maven Plugin is a Maven artifact which contains a plugin descriptor
&gt; and one or more Mojos. A Mojo can be thought of as a goal in Maven,
&gt; and every goal corresponds to a Mojo. The `compiler:compile` goal
&gt; corresponds to the `CompilerMojo` class in the Maven Compiler Plugin,
&gt; and the `jar:jar` goal corresponds to the `JarMojo` class in the Maven
&gt; Jar Plugin. When you write your own plugin, you are simply grouping
&gt; together a set of related Mojos (or goals) in a single plugin
&gt; artifact.

A Mojo simply associates with a Maven goal, so we can say a Mojo is much more than just a goal in Maven.

The [Maven site][1] says Mojo is the combination of &quot;Maven&quot; + &quot;POJO (Plain Old Java Object)&quot;. So then, MOJO = Maven Old Java Object.

But another, different answer at [Maven: The Complete Reference][2] which I think is from the same group of people that are managing the Maven site suggest Mojo is meant to mean Magical POJO.


  [1]: http://maven.apache.org/guides/introduction/introduction-to-plugins.html
  [2]: http://books.sonatype.com/mvnref-book/reference/writing-plugins-sect-programming-maven.html

- MOJO (**M**aven **O**ld **J**ava **O**bject)  is a goal in Maven.    

- In maven, everything is done by plugin, a plugin has one or more related mojos i.e. goals.  

- Mojo is single unit of task in maven.  

for example : `elicpse:eclipse` the eclipse plugin with eclipse goal is a MOJO




I&#39;m trying to follow some tutorials to learn how to use Git but some of the instructions are for specific versions.

Is there a command that I can use find out what version I have installed?

How can I find out what version of git I&#39;m running?

I don&#39;t actually know how to describe what I wanted, but I&#39;ll show you:

For example:

    $data1 = &quot;the color is&quot;;
    $data2 = &quot;red&quot;;

What should I do (or process) so $result is the combination of `$data1` and `$data2`?

Desired result:

    $result = &quot;the color is red&quot;;




How can I combine two strings together in PHP?

I&#39;m reading about Maven right now and everywhere in a text I see this word (mojo). I approximately understand what it means, but I would not refuse from a good explanation. I tried to google, but found only non-maven explanations.

POJO - ok, but MOJO? Maven Old Java Object?


What is MOJO in Maven?

<p>I'm reading about Maven right now and everywhere in a text I see this word (mojo). I approximately understand what it means, but I would not refuse from a good explanation. I tried to google, but found only non-maven explanations.</p>
<p>POJO - ok, but MOJO? Maven Old Java Object?</p>


`Class&lt;? extends Something&gt;`

Here&#39;s my interpretation, it&#39;s class template but the class ? means the name of the class is undetermined and it extends the Something class.

if there&#39;s something wrong with my interpretation, let me know.




in Java syntax, Class&lt;? extends Something&gt;

I would like to create a custom exception in Java, how do I do it?

    ...
    
    try{
    
    ...

    String word=reader.readLine();
    
    if(word.contains(&quot; &quot;))
      /*create custom exception*/
    
    }
    catch(){

   
When I create my custom exception with `throw new...`, I obtain the error `unreported exception...must be caught or declared to be thrown` 
   

How to create a custom exception type in Java?

Recently in our team we started discussing using spring annotations in code to define spring dependencies. Currently we are using context.xml to define our dependencies. Would you give me some clues for either approach, and when one is better to be used?

Edit: I know this seems a duplicate question to a more-general one, but I am interested in the impacts of annotations vs configuration for dependency injection only, which I believe would have different answers and attitude than the general question.

Spring annotation-based DI vs xml configuration?

I&#39;ve noticed this pattern in a lot of Android apps and games recently: when clicking the back button to &quot;exit&quot; the application, a &lt;code&gt;Toast&lt;/code&gt; comes up with a message similar to &quot;Please click BACK again to exit&quot;.

I was wondering, as I&#39;m seeing it more and more often, is that a built-in feature that you can somehow access in an activity? I&#39;ve looked at the source code of many classes but I can&#39;t seem to find anything about that.

Of course, I can think about a few ways to achieve the same functionality quite easily (the easiest is probably to keep a boolean in the activity that indicates whether the user already clicked once...) but I was wondering if there&#39;s something already here.

**EDIT**: As @LAS_VEGAS mentioned, I didn&#39;t really mean &quot;exit&quot; in the traditional meaning. (i.e. terminated) I meant &quot;going back to whatever was open before the application start activity was launched&quot;, if that makes sense :)

Clicking the back button twice to exit an activity

I have a List of Objects like `List&lt;Object&gt; p`.I want to sort this list alphabetically using Object name field. Object contains 10 field and name field is one of them.

    if (list.size() &gt; 0) {
        Collections.sort(list, new Comparator&lt;Campaign&gt;() {
            @Override
            public int compare(final Object object1, final Object object2) {
            return String.compare(object1.getName(), object2.getName());
            }
        } );
    }

But there is nothing like String.compare..?

How to sort a List&lt;Object&gt; alphabetically using Object name field

I have spent been on the Maven site reading the 5- and 30-minute tutorials, and trialing Maven out for the first time.

I want to install a Maven plugin and use it to start building Maven projects from Eclipse.

Despite an honest effort, I have been unable to find a comprehensive tutorial on any Maven plugin. `M2E`, which seems like the de facto standard, has nothing but broken (or recursive) links on their site.

I can&#39;t tell if I even installed the plugin correctly, or how to use it.

Does anyone know of a good step-by-step guide to `M2E` or any other plugin? One that comes with good installation documentation, along with a solid explanation of its features and proper uses?


Maven in Eclipse: step by step installation

When I load up a workspace (for Android Java development), Eclipse says in the status bar that it&#39;s updating indexes.  The Progress tab reports that it&#39;s hitting maven.org.

I read up on Maven - seems like a build manager.  What I don&#39;t understand is why my Android workspace needs it or why it&#39;s hitting the server in the cloud.  Do I need it?  If not, how do I safely remove it?

![enter image description here][1]


  [1]: http://i.stack.imgur.com/z6aXC.png

What is Eclipse doing when it says that it&#39;s updating indexes?

How can I get the maven-release-plugin to run without triggering the tests?  

I have tried

    -Dmaven.test.skip=true 
and 

    -DskipTests 
and 

    -DpreparationGoals=clean

...yet none work.


Yes, I know I shouldn&#39;t release if the tests don&#39;t pass, but I don&#39;t have control over making my coworkers write reliable tests.  



How can I get maven-release-plugin to skip my tests?

I have a fairly simple Maven project:

&lt;!-- language: xml --&gt;

    &lt;project&gt;
        &lt;dependencies&gt;
            ...
        &lt;/dependencies&gt;
    
        &lt;build&gt;
            &lt;plugins&gt;
                &lt;plugin&gt;
                    &lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
                    &lt;artifactId&gt;maven-dependency-plugin&lt;/artifactId&gt;
                    &lt;version&gt;2.4&lt;/version&gt;
                    &lt;executions&gt;
                        &lt;execution&gt;
                            &lt;id&gt;copy-dependencies&lt;/id&gt;
                            &lt;phase&gt;package&lt;/phase&gt;
                            &lt;goals&gt;
                                &lt;goal&gt;copy-dependencies&lt;/goal&gt;
                            &lt;/goals&gt;
                            &lt;configuration&gt;
                                &lt;outputDirectory&gt;${project.build.directory}/dependencies&lt;/outputDirectory&gt;
                            &lt;/configuration&gt;    
                        &lt;/execution&gt;
                    &lt;/executions&gt;
                &lt;/plugin&gt;
            &lt;/plugins&gt;
        &lt;/build&gt;
    &lt;/project&gt;

However, I get the following error in m2eclipse:

    Description	Resource	Path	Location	Type
    maven-dependency-plugin (goals &quot;copy-dependencies&quot;, &quot;unpack&quot;) is not supported by m2e. pom.xml	/jasperreports-test	line 60	Maven Project Build Lifecycle Mapping Problem

Why do I care if m2eclipse doesn&#39;t &quot;support&quot; this task? Maven does, and that&#39;s all I really care about. How can I get this error in my project to go away? 


maven-dependency-plugin (goals &quot;copy-dependencies&quot;, &quot;unpack&quot;) is not supported by m2e

I&#39;m trying to install maven through the terminal by following [these instructions][1].

So far I got this:


    export M2_HOME=/user/apple/apache-maven-3.0.3
    export M2=$M2_HOME/bin
    export PATH=$M2:$PATH
    export JAVA_HOME=/usr/java/jdk1.6.0_22

Where do you go to find this?


  [1]: http://maven.apache.org/download.html

Maven Install on Mac OS X

On Windows 7, I am trying to send the output of a **maven-3** command to a text file.

I call the command from the root of the project I am trying to analyze.

The command is:

    mvn dependency:tree -Dverbose -Dincludes=commons-collections -DoutputFile=C:\Users\myname\Documents\output.txt

When I run the command without the `outputFile` parameter, I see the output sent to the console.

But when I use it with the `outputFile` parameter, the output file is empty.

Any idea what I am missing here?

Send maven output to file

I just started using Maven and I read that plugins are additional components that can be used.   
A typical structure of `pom.xml` file is

&lt;!-- language: xml-lang --&gt;

    &lt;project&gt;
      &lt;groupId&gt;org.koshik.javabrains&lt;/groupId&gt;
      &lt;artifactId&gt;JarName&lt;/artifactId&gt; (A fldernamed JarName was created) 
      &lt;version&gt;1.0-SNAPSHOT&lt;/version&gt;
      &lt;packaging&gt;jar&lt;/packaging&gt;
    
      &lt;name&gt;JarName&lt;/name&gt;
      &lt;url&gt;http://maven.apache.org&lt;/url&gt;
    
      &lt;properties&gt;
        &lt;project.build.sourceEncoding&gt;UTF-8&lt;/project.build.sourceEncoding&gt;
      &lt;/properties&gt;
    
      &lt;dependencies&gt;
        &lt;dependency&gt;
          &lt;groupId&gt;junit&lt;/groupId&gt;
          &lt;artifactId&gt;junit&lt;/artifactId&gt;
          &lt;version&gt;3.8.1&lt;/version&gt;
          &lt;scope&gt;test&lt;/scope&gt;
        &lt;/dependency&gt;
      &lt;/dependencies&gt;
    &lt;/project&gt;

**Question**: Where should I insert a `plugin` tag? such as the following:

    &lt;plugin&gt;
      &lt;groupId&gt;org.jibx&lt;/groupId&gt;
      &lt;artifactId&gt;jibx-maven-plugin&lt;/artifactId&gt;
      &lt;version&gt;1.2.4&lt;/version&gt;
      &lt;executions&gt;
        &lt;execution&gt;
          &lt;goals&gt;
            &lt;goal&gt;bind&lt;/goal&gt;
          &lt;/goals&gt;
        &lt;/execution&gt;
      &lt;/executions&gt;
    &lt;/plugin&gt;

Before the dependency or after the `dependency` tag? Does it matter?

Plugins in Maven and POM.xml

I created a new simple Maven project in a new Workspace.

When I open the `pom.xml`&#39;s `Dependencies` view in Eclipse editor, and I choose `Add..` dependency, there&#39;s no search results no matter what search criteria I input in the search fields: 

It instantly give me, for example, `Results for &#39;spring&#39; (0)`.

In my other workspace, with my existing projects I don&#39;t have this problem.

Is there a way to fix that ?






Eclipse : Maven search dependencies doesn&#39;t work

I have a Maven web project in my repo.  

I am a Maven noob but still I understand the fact that there are plugins which we need to configure only then we could run plugin specific commands.

**Facts:**

I have a sonar server running on my local machine at port 9000.

I have not added any sonar specific plugin in my POM.xml

**Reference:**

http://www.sonarsource.org/we-had-a-dream-mvn-sonarsonar/

**Observation:**

But still when I run `mvn sonar:sonar` in my project from command line it works fine.

Matter of the fact is **I have NOT configured sonar plugin in my POM.xml Even then from where the hell Maven is picking up and understanding &quot;sonar:sonar&quot; goal/command?**

**Question / curiosity:**

I don&#39;t want the working knowledge of sonar itself. I want to know why `mvn sonar:sonar` works without configuring a sonar plugin in my pom.xml

WHY and how?

Why does the Maven command &quot;mvn sonar:sonar&quot; work without any plugin configuration in my &quot;pom.xml&quot;?

I get this error when trying to compile a Vaadin WAR:

    Failed to execute goal org.apache.maven.plugins:maven-war-plugin:2.1.1:war (default-war) on project testvaadin-web: Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/web.xml if executing in update mode) -&gt; [Help 1]

I know this error means that maven cannot find my web.xml, but in the &quot;Book of Vaadin&quot; it says that **web.xml is not needed** when using Servlet API 3.0 and the Annotation `@WebServlet` in your UI class. 

I am compiling my widgetsets in a separate profile (according to [this](http://bluegulf.wordpress.com/2012/10/18/tutorial-of-setting-up-eclipsemavenvaadinjetty-project-ide-2/) guide) and it compiles fine when I rnu this profile. However, when I compile only the web-project, I get above mentioned error.

What gives?

Do I override the maven behaviour somehow? Vaadin didn&#39;t even create a WEB-INF directory. I guess I could create WEB-INF folder and keep a &quot;ghost&quot; web.xml in there to keep maven happy, but that doesn&#39;t seem right. 

Am I missing something?

Does anyone know a good solution to this?


webxml attribute is required with Servlet 3.0

When someone writes &quot;nit: removed whitespace&quot; on a commit, what does &quot;nit&quot; mean? I&#39;ve also seen it capitalized as if it were an abbreviation (i.e. NIT). For an example usage see [this post](https://news.ycombinator.com/item?id=7357149):

&gt; Of course there is a difference between a comment saying: &quot;Nit:
&gt; Trailing whitespace&quot; and &quot;According to Section V, Subsection VII of
&gt; the Coding Manual you should never add trailing whitespace. Please see
&gt; that you don&#39;t.&quot; or some stuff like that. The latter is a
&gt; passive-aggressive potshot, the former IMO is just a quick reminder.

Other example from [&quot;Chromium Code Reviews&quot;](https://codereview.chromium.org/9662):

&gt; Issue 9662: fix minor style nit (Closed)

EDIT: And an answer comes from [Bugzilla&#39;s review page](https://wiki.mozilla.org/Bugzilla:Review):

&gt; Sometimes the reviewer will prefix his comments with &quot;Nit:&quot;. This
&gt; means that he&#39;s just &quot;nitpicking&quot;--you don&#39;t have to fix these points,
&gt; but we&#39;d like you to.

 

Content Type	Original Author	Original Content on Stackoverflow
Question	dnim	View Question on Stackoverflow
Solution 1 - Java	Lynn Crumbling	View Answer on Stackoverflow
Solution 2 - Java	Venky Vungarala	View Answer on Stackoverflow
Solution 3 - Java	Javateer	View Answer on Stackoverflow
Solution 4 - Java	Premraj	View Answer on Stackoverflow

What is MOJO in Maven?

Java Problem Overview

Java Solutions

Solution 1 - Java

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How can I combine two strings together in PHP?

How can I find out what version of git I'm running?

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