1. `Normal Class`: A Java class

2. `Java Beans`:  
 - All properties private (use getters/setters)
 - A public no-argument constructor
 - Implements Serializable.

3. `Pojo`:
Plain Old Java Object is a Java object not bound by any restriction other than those forced by the Java Language Specification. I.e., a POJO should not have to
- Extend prespecified classes
- Implement prespecified interface
- Contain prespecified annotations

POJO stands for Plain Old Java Object, and would be used to describe the same things as a &quot;Normal Class&quot; whereas a JavaBean follows a set of rules. Most commonly Beans use getters and setters to protect their member variables, which are typically set to private and have a no-argument public constructor. Wikipedia has a pretty good rundown of JavaBeans: http://en.wikipedia.org/wiki/JavaBeans

POJO is usually used to describe a class that doesn&#39;t need to be a subclass of anything, or implement specific interfaces, or follow a specific pattern.

POJO = Plain Old Java Object. It has properties, getters and setters for respective properties. It may also override `Object.toString()` and `Object.equals()`.

Java Beans : See [Wiki link][1].

Normal Class : Any java Class.


  [1]: http://en.wikipedia.org/wiki/JavaBeans

We&#39;re just starting a UNIX class and are learning a variety of Bash commands. Our assignment involves performing various commands on a directory that has a number of folders under it as well. 

I know how to list and count all the regular files from the root folder using: 

    find . -type l | wc -l

But I&#39;d like to know where to go from there in order to find the largest file in the whole directory. I&#39;ve seen somethings regarding a `du` command, but we haven&#39;t learned that, so in the repertoire of things we&#39;ve learned I assume we need to somehow connect it to the `ls -t` command.


And pardon me if my &#39;lingo&#39; isn&#39;t correct, I&#39;m still getting used to it!

How to find the largest file in a directory and its subdirectories?

I am new to Git and I am using EGit eclipse plugin to commit.

I modified few files and I stashed the changes, then I did `git pull` in command line which pulled up all the latest commits. Then I did `Apply stashed changes` from EGit. Now it applied my changes and the changes which pulled from last commit of stashed files went out. I am not sure why it didn&#39;t ask me about merge conflicts and overwrote my changes and lost previous commits changes. 

How to get those changes?

git stash and git pull

&gt; **Possible Duplicate:**  
&gt; [Difference between DTO, VO, POJO, JavaBeans?](https://stackoverflow.com/questions/1612334/difference-between-dto-vo-pojo-javabeans)  

&lt;!-- End of automatically inserted text --&gt;

Hi please don&#39;t say my question is duplicate :-) I saw all questions but didn&#39;t understand the exact difference.

Can someone explain what is `POJO`, `Bean`, `Normal Class` in easy language?



What is java pojo class, java bean, normal class?

> Possible Duplicate: 
> <a href="https://stackoverflow.com/questions/1612334/difference-between-dto-vo-pojo-javabeans" target="_blank" rel="noopener noreferrer">Difference between DTO, VO, POJO, JavaBeans?</a>

Hi please don't say my question is duplicate :-) I saw all questions but didn't understand the exact difference.
Can someone explain what is <code>POJO</code>, <code>Bean</code>, <code>Normal Class</code> in easy language?

Why does Eclipse give me the warming &quot;Resource leak: &#39;in&#39; is never closed&quot; in the following code?

    public void readShapeData() {
            Scanner in = new Scanner(System.in);
            System.out.println(&quot;Enter the width of the Rectangle: &quot;);
            width = in.nextDouble();
            System.out.println(&quot;Enter the height of the Rectangle: &quot;);
            height = in.nextDouble();

Resource leak: &#39;in&#39; is never closed

To set Background:
-------------
    RelativeLayout layout =(RelativeLayout)findViewById(R.id.background);
    layout.setBackgroundResource(R.drawable.ready);


Is the best way to do it?

How set background drawable programmatically in Android

I need a `Stack` data structure for my use case. I should be able to push items into the data structure and I only want to retrieve the last item from the Stack. The [JavaDoc for Stack][1] says :

&gt; A more complete and consistent set of LIFO stack operations is
&gt; provided by the Deque interface and its implementations, which should
&gt; be used in preference to this class. For example:

   

    Deque&lt;Integer&gt; stack = new ArrayDeque&lt;&gt;();

I definitely do not want synchronized behavior here as I will be using this datastructure local to a method . Apart from this why should I prefer `Deque` over `Stack` here ?

P.S: The javadoc from Deque says :

&gt; Deques can also be used as LIFO (Last-In-First-Out) stacks. This
&gt; interface should be used in preference to the legacy Stack class.

[1]:http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/6-b14/java/util/Stack.java#Stack

Why should I use Deque over Stack?

&gt; **Possible Duplicate:**  
&gt; [Maven Jetty plugin - how to control VM arguments?](https://stackoverflow.com/questions/2007192/maven-jetty-plugin-how-to-control-vm-arguments)  

&lt;!-- End of automatically inserted text --&gt;

In particular, I want to do something like this:

    mvn -DjvmArgs=&quot;-Xmx2000m -Xms1000m -XX:PermSize=512m -XX:MaxPermSize=512m&quot; jetty:run -Pmyprofile

Oh, and I would like to do this without having to modify the pom files or set any environment variables.. etc

Is there a way to pass JVM args via command line to Maven?

I have put log4j to my buildpath, but I get the following message when I run my application:

    log4j:WARN No appenders could be found for logger (dao.hsqlmanager).
    log4j:WARN Please initialize the log4j system properly.
    log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

What do these warnings mean?  Whats the appender here?

No appenders could be found for logger(log4j)?

I&#39;m writing some code that takes a filename, opens the file, and parses out some data. I&#39;d like to do this in a class. The following code works:

    class MyClass():
        def __init__(self, filename):
            self.filename = filename 

            self.stat1 = None
            self.stat2 = None
            self.stat3 = None
            self.stat4 = None
            self.stat5 = None

            def parse_file():
                #do some parsing
                self.stat1 = result_from_parse1
                self.stat2 = result_from_parse2
                self.stat3 = result_from_parse3
                self.stat4 = result_from_parse4
                self.stat5 = result_from_parse5

            parse_file()

But it involves me putting all of the parsing machinery in the scope of the `__init__` function for my class. That looks fine now for this simplified code, but the function `parse_file` has quite a few levels of indention as well. I&#39;d prefer to define the function `parse_file()` as a class function like below:

    class MyClass():
        def __init__(self, filename):
            self.filename = filename 

            self.stat1 = None
            self.stat2 = None
            self.stat3 = None
            self.stat4 = None
            self.stat5 = None
            parse_file()

        def parse_file():
            #do some parsing
            self.stat1 = result_from_parse1
            self.stat2 = result_from_parse2
            self.stat3 = result_from_parse3
            self.stat4 = result_from_parse4
            self.stat5 = result_from_parse5

Of course this code doesn&#39;t work because the function `parse_file()` is not within the scope of the `__init__` function. Is there a way to call a class function from within `__init__` of that class? Or am I thinking about this the wrong way?

Calling a class function inside of __init__

I&#39;m trying to load a jar using

    @echo off
    java -jar Test.jar
    pause

With the manifest of 

    Manifest-Version: 1.0
    Main-Class: classes.TestClass

In the Jar directory, I can clearly see a classes\TestClass file when I extract it.

Edit: `classes.TestClass` does have a `public static void main(String[] args)`. 

Package Deceleration in `classes.TestClass` is `package classes;`

But I still keep getting the error message 

    Could not find or load main class classes.TestClass

I&#39;ve been through everything I&#39;ve been able to find with this problem, and none of it seems to help.

I&#39;ve tried editing the classpath, redoing the manifest, installing the new JRE. 

What else should I be doing? 

Could not find or load main class with a Jar File

How do you make this work:

    public class Frankenstein&lt;T extends IHuman, IMonster&gt;{
    }

Without making 

    public interface Weirdo extends Ihuman, IMonster{
    }

**Edit**

Why is this not working?

    public &lt;T&gt; void mapThis(
    		Class&lt;? extends MyClass&lt;T&gt;&gt; key, Class&lt;? extends T &amp; IDisposable&gt; value) {
    
    }

I am getting compiler message marking `Class&lt;? extends T &amp; IDisposable&gt;` as an Error.

Java generics - Make Generic to extends 2 interfaces

I wanted to move to TypeScript from traditional JS because I like the C#-like syntax.
My problem is that I can&#39;t find out how to declare static classes in TypeScript.

In C#, I often use static classes to organize variables and methods, putting them together in a named class, without needing to instatiate an object.
In vanilla JS, I used to do this with a simple JS object:
 
    var myStaticClass = {
        property: 10,
        method: function(){}
    }

In TypeScript, I would rather go for my C-sharpy approach, but it seems that static classes don&#39;t exist in TS.
 What is the appropriate solution for this problem ?

TypeScript static classes

I constructed a class with one `String` field. Then I created two objects and I have to compare them using `==` operator and `.equals()` too. Here&#39;s what I&#39;ve done:

    public class MyClass {
    	
    	String a;
    	
    	public MyClass(String ab) {
    		a = ab;
    	}
    	
    	public boolean equals(Object object2) {
    		if(a == object2) { 
    			return true;
    		}
    		else return false;
    	}
    	
    	public boolean equals2(Object object2) {
    		if(a.equals(object2)) {
    			return true;
    		}
    		else return false;
    	}
    	
    	
    	
    	public static void main(String[] args) {
    		
    		MyClass object1 = new MyClass(&quot;test&quot;);
    		MyClass object2 = new MyClass(&quot;test&quot;);
    		
    		object1.equals(object2);
    		System.out.println(object1.equals(object2));
    		
    		object1.equals2(object2);
    		System.out.println(object1.equals2(object2));
    	}
    	
    
    }

After compile it shows two times false as a result. Why is it false if the two objects have the same fields - &quot;test&quot;?

Compare two objects with .equals() and == operator

I am trying to make my first bean in Spring but got a problem with loading a context.
I have a configuration XML file of the bean in src/main/resources.

I receive the following IOException:

&gt;Exception in thread &quot;main&quot;  org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [src/main/resources/beans.xml]; nested exception is 
    
&gt;java.io.FileNotFoundException: class path resource [src/main/resources/beans.xml] cannot 
    be opened because it does not exist

but I don&#39;t get it, since I do the following code test:

    File f = new File(&quot;src/main/resources/beans.xml&quot;);
    System.out.println(&quot;Exist test: &quot; + f.exists());

which gives me true! `resources` is in the classpath. What&#39;s wrong?


Spring cannot find bean xml configuration file when it does exist

1) Why do we use `DTO` and `DAO`, and when should we use them. I am developing a `GUI` Java software to do with inserting, editing, deleting data. But I am struggling to distinguish between `DTO/DAO` and `Model`, `View`, `Controller` (MVC)  Structure? Are they similar, which is  better to use when interacting with database through Java `GUI`. 

2) One thing I&#39;m really curious about is whether it is a good practice to have `view` and `Controller` in one class. If we think about `Netbeans`, you can create `GUI` Frame Class and add components like `JButton` onto the frame, double clicking the button will take you to the `actionListener` method(Controller) which appears to be in the frame the data is to be displayed to the user (View). So they&#39;re in the same class. Is that completely going against the concept then or not?  


 &lt;a href=&quot;http://www.youtube.com/watch?v=Iwwznm9XSME&quot;&gt;Here&lt;/a&gt; is what I&#39;m talking about

bad practice to have view and controller in one class? 

DTO and DAO concepts and MVC

I have a logback appender defined in the logback.xml, it&#39;s a DB appender, but I&#39;m curious if there is any way to configure the appender in java using my own connection pool defined as a bean. 

I find similar things, but never the actual answer. 

Programmatically configure LogBack appender

I am new to Spring MVC and have a little idea of the usage of java beans in Java.  
What is the basic difference between a Java bean and Spring bean?

Difference between JavaBean and Spring bean

I&#39;ve been looking at Jackson, but is seems I would have to convert the Map to JSON, and then the resulting JSON to the POJO. 

Is there a way to convert a Map&lt;String, String&gt; directly to a POJO?





Convert a Map&lt;String, String&gt; to a POJO

I have a Spring Data repository method with a native query

    @Query(value = &quot;SELECT g.*, gm.* FROM group g LEFT JOIN group_members gm ON g.group_id = gm.group_id and gm.user_id = :userId WHERE g.group_id = :groupId&quot;, nativeQuery = true)
    GroupDetails getGroupDetails(@Param(&quot;userId&quot;) Integer userId, @Param(&quot;groupId&quot;) Integer groupId);

and I&#39;d like to map the result to Non-Entity POJO `GroupDetails`.

Is it possible and if so, could you please provide an example ?

Content Type	Original Author	Original Content on Stackoverflow
Question	Siva	View Question on Stackoverflow
Solution 1 - Java	Kumar Vivek Mitra	View Answer on Stackoverflow
Solution 2 - Java	simap	View Answer on Stackoverflow
Solution 3 - Java	Nandkumar Tekale	View Answer on Stackoverflow

What is java pojo class, java bean, normal class?

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git stash and git pull

How to find the largest file in a directory and its subdirectories?

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