Leepoint Java Reference Notes on the Java language and its standard library.

Java, written down properly

Short notes on the language and the parts of its standard library people actually reach for. One topic per page, with the smallest example that makes the behaviour clear.

Browse the notes Set up a JDK
StringComparison.java Java 
// The mistake everyone makes once
String a = "hello";
String b = new String("hello");

a == b            // false — two different objects
a.equals(b)       // true  — same characters

// and why it appears to work with literals
String c = "hello";
a == c            // true — the compiler pools them

Before you start

What machine you actually need

Java development is not demanding. Compiling is quick, most student programs are trivial to run, and the language does not care what your machine cost. What is demanding is the tooling: an IDE indexing a project, a browser with thirty tabs, and a container or two. The three numbers that matter are memory, disk type and screen — and in that order. Nothing else on the spec sheet will change your day. Here is what each actually costs, and what to do about the payment plan the shop will offer you: match the term to how long you will keep the machine, and read the total the contract says you will pay by the end. Polish agreements print that total, Avinto among the lenders showing it, and it is the only figure that compares two offers honestly.

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