Java SE

This category will hold articles for Java SE and Eclipse.

I think Java can be a lot of fun, since it already delivers a lot out of the box.

People who develop Java APIs usually give it a lot of thinking and work.

 

Java EE in comparison to Java SE can be described as a huge collection of Frameworks and API developed around Java SE.

Java EE is not a stand-alone programming language, but based on Java SE.

 If you receive an error message similar to the below, this article might be of interest for you.

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Access restriction: The type 'CharacterEscapeHandler' is not API (restriction on required library 'C:\Program Files\Java\jdk1.7.0_25\jre\lib\rt.jar')

The error indicated that a Java internal class you are importing is actually a non API class. This means the class is only used by Java itself, but should not be used by other classes implemented in Java as Oracle does not guarantee that the class will not change by time with a newer Java version. Thus it is in general a bad design choice to use such classes and you should implement it yourself.

Internal / Non API classes can easily be identified by their package path. All classes, which reside in the package com.sun. are non API classes.

In my example I was using the following class in a XML parser.

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import com.sun.xml.internal.bind.marshaller.CharacterEscapeHandler;

Since my solution is only temporary I ignored this and found a way to ignore this error message in Eclipse as found on stackoverflow.com.

http://stackoverflow.com/questions/860187/access-restriction-on-class-due-to-restriction-on-required-library-rt-jar

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Go to the Build Path settings in the project properties.
Remove the JRE System Library
Add it back; Select "Add Library" and select the JRE System Library. The default worked for me.

 Hope it helps.

Hits: 3346

If you have to get a systems temporary directory for example to store some property files, you could use the following code.

Source Code

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String tmpDir = System.getProperty("java.io.tmpdir");

By my experience, the resulting String will already include the operating specific path separator.

Hits: 2222

I found a simple trick to add leading zeros to numbers on stackoverflow.com.

I like.

Source Code

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	@Test
	public void testLeadingZeros() {
		String formatted = String.format("%06d", 1);
		System.out.println(formatted);
	}

References

http://stackoverflow.com/questions/275711/add-leading-zeroes-to-number-in-java

Hits: 2760
  1. Replace unmatched parenthesis

Subcategories

JavaFX and e(fx)clipse Article Count:  5

This category provides articles regarding JavaFX as well as e(fx)clipse as this seems to be a good start to deal with JavaFX.

JavaFX has been around for some time now and Oracle is currently triying to enforce it as new standard for Java Rich Client Applications.

Regarding to a developer I know it has had some improvements over the years and it looks like it is going to be a try out worthy successor of AWT (Java), Swing (Java) and SWT (IBM).

However Oracle is trying to push this somewhat new technology into the market for some time now, it has not yet been accepted by the Java community.

Root cause for this seem to be the following reasons.

  • Companies are not asking for Rich Client Applications, but there is a trend for developing Web Applications. Therefore motivation to use anything like AWT, Swing, SWT or JavaFX is low except for private purposes. However JavaFX supports Mobile Applications, which is a big market. Since integration with mobiles is asked by companies as well for web applications and older technologies not supporting it, I can understand Oracle not wanting to provide support for it anymore.
  • Programmers are lazy. If you give them something completely new to learn, it takes quite an effort to get to a stage where you are as fast as using already known technologies. The standard platform for Java development, eclipse is still not providing the same comfortable "what you see is waht you get editors" for JavaFX as it is providing for the older technologies. Until eclipse is not deprecating support for Swing and older technologies like SWT and AWT they will be used by programmers.

I did some research one the internet regarding JavaFX so far but I will try to write more articles in the future about it as I intend to write little tools for myself in Java. For this I of course do not want the hustle of maintaining a JEE server all the time. Therefore JavaFX is intersting for me but I am far from beeing an expert, so try it yourself.

Eclipse SWT Article Count:  2

Groups articles regarding eclipse SWT.

Apache POI Article Count:  4

A category to collect articles around Apache POI.

Java Architecture for XML Binding (JAXB) Article Count:  3

Java Architecture for XML Binding (JAXB) provides a fast and convenient way to bind XML schemas and Java representations, making it easy for Java developers to incorporate XML data and processing functions in Java applications. As part of this process, JAXB provides methods for unmarshalling (reading) XML instance documents into Java content trees, and then marshalling (writing) Java content trees back into XML instance documents. JAXB also provides a way to generate XML schema from Java objects.