//java类型转换 public class Demo2 {	public static void main(String[] args){		int num1 = 55;		int num2 =77;		String str3 = "12355588";		String str4 = "12345222";		long lnum5 = 123991122;		long lnum6 = 99121222;		//int->string		String result1 = Integer.toString(num1)+Integer.toString(num2);		System.out.println("int->string:num1+num2="+result1);		//long->int		int result2 = (int)lnum5+(int)lnum6;		System.out.println("long->int:lnum5+lnum6="+result2);		//long->string		String result3 = Long.toString(lnum5)+Long.toString(lnum6);		System.out.println("long->string:lnum5+lnum6="+result3);		//string->int		int result4 = Integer.parseInt(str3)+Integer.valueOf(str4).intValue();		System.out.println("string->int:str3+str4="+result4);		//string->long		long result5 = Long.parseLong(str3)+Long.valueOf(str4);		System.out.println("string->long:str3+str4="+result5);	}