java8函数式编程内置函数小结

java8函数式编程 Function

        // Function -T作为输入，返回的R作为输出 
        Function function = (x) -> {System.out.print(x+": ");return "Function";};
        System.out.println(function.apply("hello world"));
        
        //Predicate -T作为输入，返回的boolean值作为输出 
        Predicate pre = (x) ->{System.out.print(x);return false;};
        System.out.println(": "+pre.test("hello World"));
        
        //Consumer - T作为输入，执行某种动作但没有返回值 
        Consumer con = (x) -> {System.out.println(x);};
        con.accept("hello world");
        
        //Supplier - 没有任何输入，返回T 
        Supplier supp = () -> {return "Supplier";};
        System.out.println(supp.get());
        
        //BinaryOperator -两个T作为输入，返回一个T作为输出，对于“reduce”操作很有用 
        BinaryOperator bina = (x,y) ->{System.out.print(x+" "+y);return "BinaryOperator";};
        System.out.println("  "+bina.apply("hello ","world"));

// 输出
hello world: Function
hello World: false
hello world
Supplier
hello  world  BinaryOperator