Need a Java refresher?

It's amazing to hear that Java is 20 years old already.
If you used it and took a break and now want to get back into Java again, the following link could help as a learning refresher:

JavaWorld: Learn Java from the ground up

Java 20th anniversary #Java20

Update Your Skills for the 20 Years of Java

Overcome Java JNI gdb errors on GNU/Linux

If you happen to try to debug any Java JNI programs using gdb on GNU/Linux you will soon come across error messages. For example : $ gdb --args java MyJavaProgramUsingJNI cannot find user-level thread for LWP nnn: generic error warning: Cannot initialize thread debugging library: versions of libpthread and libthread_db do not match The reason for this is that the java program mucks around with LD_LIBRARY_PATH and that prevents gdb from running correctly. To overcome this, you have to run your Java program and place a pause in the Java code, such as reading a key, and then in another shell, run gdb to attach to the running Java process. You can then set your breakpoint on your JNI code and debug it. Here is an example : Compile your Java program: $ javac JNITest.java Generate the JNI header file: $ javah -jni JNITest.java Create and compile your C code library: $ cat jnilib.c #include "JNITest.h" JNIEXPORT jint JNICALL Java_JNITest_addValues( JNIEnv...

JNI vs. JNA, which is best for you?

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JNI is now deprecated?

JEP draft: Prepare to Restrict The Use of JNI article placeholder If enough people want this article, I will write about it and how you can use the new API instead of using JNI.

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