Java Error opening registry key

Make sure you remove any java.exe, javaw.exe and javaws.exe from your Windows\System32 folder and if you have an x64 system (Win 7 64 bits) also do the same under Windows\SysWOW64. If you can’t find them at these locations, try deleting them from C:\ProgramData\Oracle\Java\javapath.

How can I create an utility class?

For a completely stateless utility class in Java, I suggest the class be declared public and final, and have a private constructor to prevent instantiation. The final keyword prevents sub-classing and can improve efficiency at runtime. The class should contain all static methods and should not be declared abstract (as that would imply the class is not concrete and has to be implemented in … Read more

java howto ArrayList push, pop, shift, and unshift

ArrayList is unique in its naming standards. Here are the equivalencies: Note that unshift does not remove an element, but instead adds one to the list. Also note that corner-case behaviors are likely to be different between Java and JS, since they each have their own standards.

Difference between OpenJDK and Adoptium/AdoptOpenJDK

In short: OpenJDK has multiple meanings and can refer to: free and open source implementation of the Java Platform, Standard Edition (Java SE) open source repository — the Java source code aka OpenJDK project prebuilt OpenJDK binaries maintained by Oracle prebuilt OpenJDK binaries maintained by the OpenJDK community AdoptOpenJDK — prebuilt OpenJDK binaries maintained by community (open source … Read more

How do I use the JAVA_OPTS environment variable?

JAVA_OPTS is the standard environment variable that some servers and other java apps append to the call that executes the java command. For example in tomcat if you define JAVA_OPTS=’-Xmx1024m’, the startup script will execute java org.apache.tomcat.Servert -Xmx1024m If you are running in Linux/OSX, you can set the JAVA_OPTS, right before you call the startup script by doing This will … Read more

imageio.IIOException: Can’t read input file

Have you tried using new File(“logo.jpg”); (without the leading /)? And are you sure, the logo.jpg is copied to your output? (Some IDEs don’t copy every file from your source-directories to your output (or target) directories.) becomes (Note that the IDE/compiler does not copy the image to your output-directory and so the compiled code cannot … Read more

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)