package src.java8.bitwise;
/**
* @author shi.likun
* @create 2021-01-06 14:59
*/
public class Permission {
/**是否允许查询 二进制第一位,0 否 1是*/
public static final int ALLOW_SELECT = 1<<0; //0001 = 1
/**是否允许新增 二进制第二位,0 否 1是*/
public static final int ALLOW_INSERT = 1<<1;//0010 = 2
/**是否允许修改 二进制第三位,0 否 1是*/
public static final int ALLOW_UPDATE = 1<<2;//0100 = 4
/**是否允许删除 二进制第四位,0 否 1是*/
public static final int ALLOW_DELETE = 1<<3;//1000 = 8
/**存储目前的状态*/
private int flag;
/**设置用户权限*/
public void setPer(int per){
flag = per;
}
/**增加用户权限(1个或者多个)*/
public void enable(int per){
flag = flag|per;
}
/**删除用户权限(1个或者多个)*/
public void disable(int per){
flag = flag&~per;
}
/**判断用户的权限*/
public boolean isAllow(int per){
return ((flag&per) == per);
}
/**判断用户没有的权限*/
public boolean isNotAllow(int per){
return ((flag&per) == 0);
}
public static void main(String[] args) {
int flag = 15;//二进制1111,拥有所有权限
Permission permission = new Permission();
permission.setPer(flag);
permission.disable(ALLOW_DELETE|ALLOW_INSERT);
System.out.println("select = " + permission.isAllow(ALLOW_SELECT));
System.out.println("update = " + permission.isAllow(ALLOW_UPDATE));
System.out.println("insert = " + permission.isAllow(ALLOW_INSERT));
System.out.println("delete = " + permission.isAllow(ALLOW_DELETE));
}
}
