well in class level you can only define attributes of that class, cant do any processing which you are doing in classA and classB. Processing can only be done in method. Just add main method make objects there Main method is entry point of any program in java. Dont worry if you are confused where … Read more
The error message tells you that the class version is different. In other words, the Java compiler you used in Eclipse is newer than the Java runtime you use in the command prompt. You should check which Java version you want then use only this version. To change the version you use in the command … Read more
What is wrong with the code there are lots of error while debugging. I am writing a code for a singleton class to connect with the database mysql. Here is my code I am new to java. Please help.
Add() works like an insertWithPriority. You can define priority for the type that you want using the constructor: look under https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/PriorityQueue.html The order the Comparator gives will represent the priority in the queue.
Two options: Create a list of values you wish to remove, adding to that list within the loop, then call originalList.removeAll(valuesToRemove) at the end Use the remove() method on the iterator itself. Note that this means you can’t use the enhanced for loop. As an example of the second option, removing any strings with a … Read more
Go to URL in your browser: firefox – click on HTTPS certificate chain (the lock icon right next to URL address). Click “more info” > “security” > “show certificate” > “details” > “export..”. Pickup the name and choose file type example.cer chrome – click on site icon left to address in address bar, select “Certificate” … Read more
Put your code in a method. Try this: Then “run” the class from your IDE
You need to configure your environment variables, JAVA_HOME and PATH. JAVA_HOME must contain the path to java, and you should add %JAVA_HOME%\bin to PATH Alternatively, you can simply add to your PATH the whole path to the bin folder, without the JAVA_HOME variable, however, this makes a little more annoying when you need to have … Read more
Normally, I use this in constructors only. I understand that it is used to identify the parameter variable (by using this.something), if it have a same name with a global variable. However, I don’t know that what the real meaning of this is in Java and what will happen if I use this without dot … Read more
I think it’s a historical thing – if a package is introduced as an addition to an existing JRE, it comes in as javax. If it’s first introduced as part of a JRE (like NIO was, I believe) then it comes in as java. Not sure why the new date and time API will end … Read more