关于字符串连接操作符（三）(源自IBM蓝色之路一道笔试题目)
再看下下面的例子

public class TestChar1 {       public static void main(String[] args) {  // int类型的常量可以赋值给任意类型的变量        byte b = (int) 1;   //OK        short s = (int) 1;  //OK         int i = (int) 1;    //OK        long l = (int) 1;   //OK        float f = (int) 1;  //OK         double d = (int) 1; //OK          char c = (int) 1;   //OK    }   } public class TestChar2 {       public static void main(String[] args) {  // int类型的变量只能赋值给高类型的变量，不能赋值给低类型的变量（会损失精度）                 int a = 1;         char c = (int) a;              // Type mismatch: cannot convert from int to char                byte b = (int) a;              // Type mismatch: cannot convert from int to char         short s = (int) a;                // Type mismatch: cannot convert from int to char        int i = (int) a;   //OK        long l = (int) a;  //OK         float f = (int) a; //OK          double d = (int) a;//OK                  }   }public class TestChar3 {         public static void main(String [] args) {             int i = 1;                  // Type mismatch: cannot convert from int to char        char c = i;           System.out.println(c);       }   } public class TestChar4 {         public static void main(String [] args) {             char c = (int)1; //Ok, 等价于： char c='\001';          char d = '\001'; //OK        System.out.println(c==d); //output: true    }   }