Java – String, String Buffer and String Builder Classes

Creating strings:

String greeting = "Hello World";

public class StringDemo{
public static void main(String[] args)
{
char[] helloArray={'he','e','l','l','o','.'};
String helloString=new String(helloArray);
System.out.println(helloString);
}

}

output: hello
StringBuffer:
public StringBuffer append append(String s)
public stringBuffer append(boolean b)
public StringBuffer append(char c)
replace(),delete(), reverse(),capacity(),length(),setCharAt(int index,char ch),setLength(),String subString(int start),String subString(int start,int end)

one example in buffer class:

length() and capacity() method

public class StringBufferDemo {
public static void main(String[] args)
{
	StringBuffer sb=new StringBuffer("Hello");
	System.out.println("buffer = "+sb);
	System.out.println("length = "+sb.length());
	System.out.println("capacity = "+sb.capacity());
}
}

output:

buffer = Hello
length = 5
capacity = 21

For more example:
I will see in future
– Java the complete reference(Best examples here)
– Oracle Java Library
– Android Reference
– Tutorials point for explanation