Epsilon is your &quot;fuzz factor,&quot; since doubles may not be exactly equal. Epsilon lets you describe how close they have to be.

If you were expecting 3.14159 but would take anywhere from 3.14059 to 3.14259 (that is, within 0.001), then you should write something like

    double myPi = 22.0d / 7.0d; //Don&#39;t use this in real life!
    assertEquals(3.14159, myPi, 0.001);

(By the way, 22/7 comes out to 3.1428+, and would fail the assertion. This is a good thing.)

I&#39;ve a form as

    &lt;form  onSubmit=&quot;return disableForm(this);&quot; action=&quot;upload.php&quot; method=&quot;post&quot; name=&quot;f&quot; id=&quot;wizecho&quot; enctype=&quot;multipart/form-data&quot;&gt;
        &lt;input type=&quot;file&quot; name=&quot;file&quot; /&gt;
        &lt;button onClick=&quot;return disableForm(this),ajaxUpload(this.form,&#39;wizecho_upload.php&#39;, &#39;&amp;lt;br&amp;gt;Uploading image please wait.....&amp;lt;br&amp;gt;&#39;); return false;&quot;&gt;
        	Upload Image
        &lt;/button&gt;
    &lt;/form&gt;

It is to upload an image.

Here I need to click on the button to upload the image and I&#39;ve to use `onClick` event. I want to remove the upload button and as soon as the file is selected at the input, I want to fire the event. How do I do that??

how to fire event on file select

I&#39;m a newb to back-end code and I&#39;m trying to create a function that will respond to me a JSON string. I currently have this from an example

    function random(response) {
      console.log(&quot;Request handler &#39;random was called.&quot;);
      response.writeHead(200, {&quot;Content-Type&quot;: &quot;text/html&quot;});
      
      response.write(&quot;random numbers that should come in the form of json&quot;);
      response.end();
    }

This basically just prints the string &quot;random numbers that should come in the form of JSON&quot;. What I want this to do is respond with a JSON string of whatever numbers. Do I need to put a different content-type? should this function pass that value to another one say on the client side?

Thanks for your help!

Responding with a JSON object in Node.js (converting object/array to JSON string)

&gt; **Possible Duplicate:**  
&gt; [JUnit: assertEquals for double values](https://stackoverflow.com/questions/5686755/junit-assertequals-for-double-values)  

&lt;!-- End of automatically inserted text --&gt;

Apparently the `assertEquals(double expected, double actual)` has been deprecated. 

The javadocs for JUnit are surprisingly lacking, considerings its wide use. Can you show me how to use the new `assertEquals(double expected, double actual, double epsilon)`?

JUnit assertEquals(double expected, double actual, double epsilon)

> Possible Duplicate: 
> <a href="https://stackoverflow.com/questions/5686755/junit-assertequals-for-double-values" target="_blank" rel="noopener noreferrer">JUnit: assertEquals for double values</a>

Apparently the <code>assertEquals(double expected, double actual)</code> has been deprecated.
The javadocs for JUnit are surprisingly lacking, considerings its wide use. Can you show me how to use the new <code>assertEquals(double expected, double actual, double epsilon)</code>?

I have two `ArrayList` objects with three integers each. I want to find a way to return the common elements of the two lists. Has anybody an idea how I can achieve this? 

Common elements in two lists

I have added a **2.45mb** jar file to my Android eclipse project and now I continue to get &quot;Conversion to Dalvik format failed: Unable to execute dex: Java heap space&quot; no matter what I do. 

I have researched online, and was informed to update my eclipse.ini to increase my Java VM heapsizes. I have done this for all the values in eclipse.ini and I continue to get the build error.

Any ideas?

Conversion to Dalvik format failed: Unable to execute dex: Java heap space

Is the same JVM used by all Java applications running or, does &#39;one JVM per Java application&#39; apply? (say the applications are IntelliJ IDEA, a server and NetBeans for example)

Further, is there any connection between JVMs assigned and processes used by each Java application?


Is there one JVM per Java application?

I want to use logs in my program. I heard about [java.util.logging](https://docs.oracle.com/javase/8/docs/api/java/util/logging/package-summary.html), but I don&#39;t know how to begin.

Are there any examples of what can I do with logging? How would I use logging in my own program?

Good examples using java.util.logging

What&#39;s the correct approach to log both an error message and an exception using [SLF4J][1]?

I&#39;ve tried doing this but the exception stack trace is never printed:

`logger.error(&quot;Unable to parse data {}&quot;, inputMessage, e);`

In this case I want to populate `{}` with the `inputMessage` as well as logging out the exception stacktrace.

The only way I can see to do this would be to do this:

`logger.error(&quot;Unable to parse data &quot; + inputMessage, e);`

which is not pretty.


  [1]: http://www.slf4j.org/

How to log exception and message with placeholders with SLF4J

I&#39;m a newbie to unit testing and Junit. I know the basics of Junit. I just started learning about the EasyMock framework.

I couldn&#39;t understand the use of `replay()` method.

Could anyone please provide some info?

I understand the use of `EasyMock.expect()` and `EasyMock.verify()`.

What is EasyMock.replay() used for?

I have an Integration Test Suite. I have a `IntegrationTestBase` class for all my tests to extend. This base class has a `@Before` (`public void setUp()`) and `@After` (`public void tearDown()`) method to establish API and DB connections. What I&#39;ve been doing is just overriding those two methods in each testcase and calling `super.setUp()` and `super.tearDown()`. However this can cause problems if someone forgets to call the super or puts them at the wrong place and an exception is thrown and they forget to call super in the finally or something.

What I want to do is make the `setUp` and `tearDown` methods on the base class `final` and then just add our own annotated `@Before` and `@After` methods. Doing some initial tests it appears to always call in this order:

    Base @Before
    Test @Before
    Test
    Test @After
    Base @After

but I&#39;m just a little concerned that the order isn&#39;t guaranteed and that it could cause problems. I looked around and haven&#39;t seen anything on the subject. Does anyone know if I can do that and not have any problems?

Code:

    public class IntegrationTestBase {

        @Before
        public final void setUp() { *always called 1st?* }

        @After
        public final void tearDown() { *always called last?* }
    }


    public class MyTest extends IntegrationTestBase {

        @Before
        public final void before() { *always called 2nd?* }

        @Test
        public void test() { *always called 3rd?* }

        @After
        public final void after() { *always called 4th?* }
    }


What order are the Junit @Before/@After called?

I am working on a project using Maven and Eclipse (m2eclipse plugin). I&#39;ve got problems with the JUnit tests: 

Sometimes, when running them within Eclipse, they wont be compiled, but the old class files are used instead. When I delete the class files, I get `ClassNotFoundExceptions` in Eclipse. I then have to manually recompile them by using `mvn test-compile` or other goals. 

I also noticed that the class files of the tests sometimes are put into the `classes` subdirectory instead of `test-classes`.

I really can&#39;t figure out what is wrong.

The JUnit java files are within `src/main/java` and are correctly named (`*Test.java`). 

Do I have to compile and run them always via Maven? Why doesn&#39;t Eclipse compile the files when I want to run them? (Interestingly, *sometimes* it does. Sometimes everything works perfectly.)

Eclipse/Maven: JUnit tests not compiled when running them

I&#39;m using JUnit 4. I can&#39;t see the difference between initializing in the constructor or using a dedicated init function annotated by `@Before`. Does this mean that I don&#39;t have to worry about it?

Is there any case when `@Before` gives more than just initializing in the constructor?

JUnit: using constructor instead of @Before

How do I create a new `URL` object using a local file, for the purpose of unit tests?

Content Type	Original Author	Original Content on Stackoverflow
Question	LuxuryMode	View Question on Stackoverflow
Solution 1 - Java	rajah9	View Answer on Stackoverflow

JUnit assertEquals(double expected, double actual, double epsilon)

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Java Solutions

Solution 1 - Java

Responding with a JSON object in Node.js (converting object/array to JSON string)

how to fire event on file select

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