Tutoring comp sci, you experiment a lot. The tutor shares one. The java command, in Windows, anyway, seems to like a space between the directory and the filename you are running. java -cp f:/dir1/dir2 program_file not java -cp f:/dir1/dir2/program_file Source: …

Java: running program when path not set Read more »

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Tutoring Java programming, you might be asked to clarify about overriding. The tutor shares some thoughts. In Java, when you override a method, you either define its performance (give it a “body”), or else redefine (change) its performance . Case …

Java: overriding methods: what it means, and rules about it Read more »

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Tutoring Java programming, this error message might come up. The tutor talks about a couple of its causes. The message error: non-static method MethodX() cannot be referenced from a static context has a couple of causes I know: The class …

Java compile error: non-static method cannot be referenced from a static context – what causes it? Read more »

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Tutoring Java programming, there are so many interesting facets to encounter. The tutor talks about a constructor of a subclass and the word super. Let’s imagine you write a subclass. Furthermore, let’s imagine the parent class (the superclass) has a …

Java programming: constructors in subclasses Read more »

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The tutor comments on JavaScript null and undefined. Null, it seems, is often mentioned in computer science. Perhaps it’s used a little loosely: it might refer to the value read when there’s nothing there, or the value of a variable …

Computer science: JavaScript: null value, undefined type and value Read more »

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The tutor brings up a couple of “emergency procedures” for stopping a program. I don’t write many big programs; rather, I’ll often write a page or so of code (with lots of white space) to test a utility from a …

Comp Sci: command prompt testing (Windows 7): how to kill a runaway program Read more »

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The tutor looks into passing null as an argument. Sometimes, reading Java code, you encounter null being passed as an argument aka parameter: method0(null); Apparently, when a method expects an object parameter, but doesn’t (necessarily) use it, you can pass …

Java: why null might be used as an input parameter (aka argument) Read more »

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