Underlying mechanism of String pooling in Java?

Question

I was curious as to why Strings can be created without a call to new String(), as the API mentions it is an Object of class java

Answer 1

That's not tightly related to the subject, but whenever you have doubts as to what will java compiler do, you can use the

javap -c CompiledClassName

to print what is actually going on. (CompiledClassName from the dir where CompiledClassName.class is)

To add to Jesper's answer, there are more mechanisms at work, like when you concatenate a String from literals or final variables, it will still use the intern pool:

String s0 = "te" + "st";
String s1 = "test";
final String s2 = "te";
String s3 = s2 + "st";
System.out.println(s0==s1); //true
System.out.println(s3==s1); //true

But when you concatenate using non-final variables it will not use the pool:

String s0 = "te";
String s1 = s0 + "st";
String s2 = "test";
System.out.println(s1 == s2); //false