Common classes and methods of Java

Below we introduce common methods of common classes and classes provided by Java class Library

First, java.lang.String

1. Constructors common to the string class

Public String(string original)

Create a String object using the String object original, where original can be a string constant or a string object

Public String (char value[])

Create a String object using the character array value

Public String (char value[],int offset,int count)

Creates a string object with count characters starting with the character array value subscript as offset

Public String (stringbuffer buffer)

Create a String object using the object buffer of the StringBuffer class

Our upper and lower code:

1  Packagecom.learn.chap04.sec05;2 3  Public classString1 {4      Public Static voidMain (string[] args) {5String S1 =new String ("ASCD");6String s2 =new String (S1);7         8         Char[] Value =New Char[]{' A ', ' B ', ' C '};9String s3 =new String (value);   //copy entire arrayTenString S4 =new String (value,1,2); //Create the string "BC" One System.out.println (S1); A System.out.println (S2); - System.out.println (S3); - System.out.println (S4); the     } -}

Operation Result:

Ascd
Ascd
Abc
Bc

Common classes and methods of Java