Archive for coding

How to modify a class file

You can follow these steps to modify your java class:

  1. Decompile the .class file as you have done and save it as .java
  2. Create a project in Eclipse with that java file, the original JAR as library, and all its dependencies
  3. Change the .java and compile
  4. Get the modified .class file and put it again inside the original JAR.

Java Calendar format eclipse-ben

The following effectively overwrites the toString() method for any class as seen using the Eclipse Debugger only, but I’ve found it very useful in decoding calendar objects while I debug.

Add a Debug Detail Formatter, using these steps:

  1. From the menu select Windows->Preferences
  2. In Preferences open Java->Debug and click on Detail Formatters
  3. Here you can add your desired formatter

As an example, for the calendar object:

  1. Click Add..
  2. Enter java.util.Calendar into the Qualified type name field
  3. Enter the following:

java.text.SimpleDateFormat sdf = new java.text.SimpleDateFormat(“EEE, d MMM yyyy HH:mm:ss Z”); sdf.format(this.getTime());

  1. Ensure Enable this detail formatter is checked

Click OK.



eclipse/sts maven run problem

ha a hiba:

-Dmaven.multiModuleProjectDirectory system propery is not set Check $M2_HOME environment variable and mvn script match.



Window–> Preference –> Java –> Installed JREs –> Edit In the edit Default VM arguments you need to put If you already set the maven home. -Dmaven.multiModuleProjectDirectory=M2_HOME (For Windows machine) -Dmaven.multiModuleProjectDirectory=$M2_HOME (For Mac OS X)



Eclipse Maven problem

In the edit Default VM arguments you need to put

If you already set the maven home.


Eclipse pin to taskbat-vm C:\Program Files\Java\jre7\bin

Annyit szívtam már ezzel és mindig guglizni kellett, ezért leírom ide is:



Apache Solr Bad Request – FULL HEAD hiba

midne a ket esetben a HTTP request size a problémás.


Jett: FULL HEAD a hiba

Tomcat eseteben: Bad Request


kesőbb kifejtem.

Maven install



Java target definiálása Maven projektben

POM-ba tenni:

FONTOS: JAVA_HOME_8 környezeti változó mutasson a JDK8-ra.

m2-subclipse telepítése subclipse >=1.08 verziószámból

Ha az alábbi hibát kapjuk az eclipse-ben telepítéskor (Preferences->MAven->Discovery->

ha érezzük az erőt:

chackout and build

Majd install:

Help->New Software-> local es a < a kichckoutolt repo helye> /org.sonatype.m2e.subclipse.feature/target/site/

vagy a zip: m2-subclipse

vagy eclipse update site:

C# Button Background, Foreground kep csereje kodban