JVM 中字段访问指令

た入场券 2022-09-03 14:27 98阅读 0赞

# 一 字段访问指令 #

<table> 
 <tbody> 
  <tr> 
   <td> <p>字段访问指令</p> </td> 
   <td> <p>含义</p> </td> 
  </tr> 
  <tr> 
   <td> <p>getstatic、putstatic</p> </td> 
   <td> <p>访问类字段（static字段，或者称为类变量）的指令</p> </td> 
  </tr> 
  <tr> 
   <td> <p>getfield、 putfield</p> </td> 
   <td> <p>访问类实例字段（非static字段，或者称为实例变量）的指令</p> </td> 
  </tr> 
 </tbody> 
</table>

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70][]

**第一步**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 1][]

**第二步**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 2][]

**第三步**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 3][]

## 二 实战 ##

## 1 代码 ##

public void setOrderId() {
        Order order = new Order();
        order.id = 1001;
        System.out.println(order.id);
    
        Order.name = "ORDER";
        System.out.println(Order.name);
    }
    
    class Order {
        int id;
        static String name;
    }

## 2 图解 ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70 4][]

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