Table of contents
(1)Definition format
After JDK1.5, a new keyword type-enum was introduced, which can directly define enumeration types. The format is as follows:
[punlic] enum enumeration type name{ Enumeration object 1, enumeration object 2, enumeration object 3, enumeration object n...; }
(2) Requirement: Obtain the contents of an enumeration
Requirement: Get the contents of an enumeration
Code:
package com.geoji_meiju;
public enum Color {
RED,GREEN,BLUE; //定义三个枚举类型
}
package com.geoji_meiju;
public class GetEnum {
public static void main(String[] args) {
Color color=Color.BLUE; //获取枚举中的内容
System.out.println(color);
System.out.println("-----------------------------------------------------------");
for (Color color1 :Color.values() ) {
//获取枚举中的全部内容
System.out.println(color1);
}
}
}
operation result:
(3) Requirement: Combined with enumeration to achieve one login
Requirement: Combined with enumeration to achieve one login
package com.geoji_meiju;
public enum MessageEnum {
LOGIN_SUCCESS("登录成功", true),
LOGIN_USER_FAILD("登录失败用户名错误", false),
LOGIN_USER_NULL("登录失败用户名为空",false),
LOGIN_PWD_FAILD("登录失败密码错误", false),
LOGIN_PWD_NULL("登录失败用户名为空", false);
private String msg;// 消息的内容
private boolean flag;// 失败和成功
private MessageEnum(String msg, boolean flag) {
this.msg = msg;
this.flag = flag;
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
public boolean isFlag() {
return flag;
}
public void setFlag(boolean flag) {
this.flag = flag;
}
}
package com.geoji_meiju;
public class UserServce {
/**
*
* @param name
* @param pwd
* @return 在这里拿到用户和密码后，进行判断属于哪个错误，最后返回。
*/
public MessageEnum login_enum(String name , String pwd){
MessageEnum flag = null; //获取枚举中的内容
String UserName="xiaoming"; //定义账号和密码
String Pwd="123456";
if (name == null) {
flag = MessageEnum.LOGIN_USER_NULL;
}else if (!name.equals(UserName)) {
flag = MessageEnum.LOGIN_USER_FAILD;
}else if (pwd == null) {
flag = MessageEnum.LOGIN_PWD_NULL;
}else if (!pwd.equals(Pwd)) {
flag = MessageEnum.LOGIN_PWD_FAILD;
}else {
flag = MessageEnum.LOGIN_SUCCESS;
}
return flag;
}
}
package com.geoji_meiju;
public class Text {
public static void main(String[] args) {
UserServce userServce=new UserServce();
MessageEnum login=userServce.login_enum("xiaoming", "465789"); //输入用户名和密码
//输入错误的密码
System.out.println(login.getMsg()); // 获取登录信息
}
}
operation result:
