一些经常忽略的东西

>>> 无符号右移，<< 左移  >> 右移

    org.openjdk.jol
    jol-core
    0.16

public class OperatorTest {
    @Data
    @AllArgsConstructor
    @NoArgsConstructor
    static
    class Person{
        private Integer age;
        private String name;
    }
 
    /**
     * java 对象 分为对象头，class pointer ，实例数据，对齐
     * @param args
     */
    public static void main(String[] args) {
        System.out.println(Integer.toBinaryString(-8));//11111000 100010000
        System.out.println(Integer.toBinaryString(-8<<2));
        System.out.println(Integer.toBinaryString(-64));
        System.out.println(Integer.toBinaryString(-64>>>2));
        System.out.println(ClassLayout.parseInstance(10)); // 8 + 4 + 4 = 15
        System.out.println(ClassLayout.parseInstance(10l)); // 8 + 4 + 8 + 4 =24
 
        System.out.println(ClassLayout.parseInstance(false)); // 8 + 4 + 1 + 5 = 16 
        String s = new String("中");
        System.out.println(ClassLayout.parseInstance(s));
        System.out.println(ClassLayout.parseInstance("中"));
        System.out.print(ClassLayout.parseInstance(new Person(20,"zhangsan")));
 
    }
}

11111111111111111111111111111000
11111111111111111111111111100000
11111111111111111111111111000000
111111111111111111111111110000
java.lang.Integer.value @12 (int, 4b)
size = 16
 
java.lang.Long.value @16 (long, 8b)
size = 24
 
java.lang.Boolean.value @12 (boolean, 1b)
size = 16
 
java.lang.String.value @12 (byte[], 4b)
java.lang.String.hash @16 (int, 4b)
java.lang.String.coder @20 (byte, 1b)
size = 24
 
java.lang.String.value @12 (byte[], 4b)
java.lang.String.hash @16 (int, 4b)
java.lang.String.coder @20 (byte, 1b)
size = 24
 
com.example.demo.OperatorTest.Person.age @12 (java.lang.Integer, 4b)
com.example.demo.OperatorTest.Person.name @16 (java.lang.String, 4b)
size = 24
 
Process finished with exit code 0