Java string handling



In the last tutorial we have studied the basics of String in Java Programming. In this Chapter we will focus on String Literals in Java Programming.

A. String Literals in Java :

In Simple words, we can say that String Literal is Sequence of characters written in double quotes.

class FirstProgram {
public static void main(String[] args) {
   System.out.println("Hello World");
   }
}

In the above example we can say that String – “Hello World” written inside “System.out.println” will be called as String Literal.

B. String Literals is used to Create and Initialize String Object :

We know that in Java Programming, String is considered as Object not an array like C/C++.

class FirstProgram {
public static void main(String[] args) {
   String name = "Pritesh";
   System.out.println("Hello " + name + "!")
   }
}

Output of the Program :

Hello Pritesh !

Lets See how String Literal Works.

C. Working of String Literals :

JVM always maintains a String Constant Pool. If we declared a String and initialized it with String literal then String will be searched in String Constant Pool.

class FirstProgram {
public static void main(String[] args) {
   String Str1;
   String Str2 = "Hello";
   }
}

Consider above program we can see, String “Hello” will be created inside “String Constant Pool” and then reference to that String is being assigned to a String Object “Str2”.

Consider the below program –

class FirstProgram {
public static void main(String[] args) {
   String Str1 = "Hello";
   String Str2 = "Hello";
   }
}

In this program, Only Single Object will be created inside Constant Pool and reference to that String will be returned to both Objects Str1 and Str2.
String Literals to 2 String Objects

D. Unicode Characters in Literals

In order to print PI Symbol we can use following Syntax –

class FirstProgram {
public static void main(String[] args) {
   String Str1 = "u03C0";
   System.out.println(Str1);
   }
}

Similarly we can print multiple unicode characters in Java.