View Compilation Error

0_0_22149984_29569.cpp:2:8: error: expected ':' before 'static'
 public static void main(String args[]){
        ^
0_0_22149984_29569.cpp:2:25: error: 'String' has not been declared
 public static void main(String args[]){
                         ^
0_0_22149984_29569.cpp:6:1: error: expected ';' after class definition
 }
 ^
0_0_22149984_29569.cpp: In static member function 'static void caculate::main(int*)':
0_0_22149984_29569.cpp:4:2: error: 'System' was not declared in this scope
  System.out.println("a+b");
  ^