2. ConstantValue

ConstantValue属性用于表示field_info中的静态变量的初始值，结构如下：

ConstantValue_attribute {
    u2 attribute_name_index;
    u4 attribute_length;
    u2 constantvalue_index;
}

ConstantValue解析代码片段：

// 创建属性Map
Map<String, Object> attrMap = new LinkedHashMap<>();
// u2 constantvalue_index;
attrMap.put("constantValue", getConstantPoolValue(dis.readUnsignedShort()));
attributeMap.put("ConstantValue", attrMap);

解析后的结果如下：

{
  "access": 26, 
  "name": "serialVersionUID", 
  "desc": "J", 
  "attributesCount": 1, 
  "attributes": {
    "attributeName": "ConstantValue", 
    "attributeLength": 2, 
    "ConstantValue": {
      "constantValue": -7366591802115334000
    }
  }
}