class TestStringMethod
{
	public static void main(String[] args) 
	{
		String s = new String( "Hello World" );

		System.out.println( s.length() );
		System.out.println( s.indexOf('o') );
		System.out.println( s.indexOf("He") );
		System.out.println( s.startsWith("He") );
		System.out.println( s.equals("Hello world") );
		System.out.println( s.equalsIgnoreCase("Hello world") );
		System.out.println( s.compareTo("Hello Java") );
		System.out.println( s.charAt(1) );
		System.out.println( s.substring(0,2) );
		System.out.println( s.substring(2) );
		System.out.println( s.concat("!!!") );
		System.out.println( s.trim() );
		System.out.println( s.toUpperCase() );
		System.out.println( s.toLowerCase() );
		System.out.println( s.replace('o', 'x' ) );
		
		System.out.println( s );  //注意，s本身沒有改變
	}
}