Tutorial #9 : String

Strings in Java are Objects that are backed internally by a char array. Strings are immutable as well. Whenever a change to a String is made, an entirely new String is created.

Syntax:

 String_Type> <string_variable> = “<sequence_of_string>”;

Whenever a String Object is created, two objects will be created- one in the Heap Area and one in the String constant pool and the String object reference always points to heap area object.

CharBuffer: This class implements the CharSequence interface. This class is used to allow character buffers to be used in place of CharSequences.

StringBuffer: StringBuffer is a peer class of String that provides much of the functionality of strings. String represents fixed-length, immutable character sequences while StringBuffer represents growable and writable character sequences. 

StringBuilder: The StringBuilder in Java represents a mutable sequence of characters. Since the String Class in Java creates and immutable sequence of characters, the StringBuilder class provides an alternate to String Class, as it creates a mutable sequence of characters.

For example:

String str = "Amogh";

• String literal

  String s = “GeeksforGeeks”;

• Using new keyword

  String s = new String (“GeeksforGeeks”);