Search...
FAQs
Subscribe
Pie
FAQs
Recent topics
Flagged topics
Hot topics
Best topics
Search...
Search Coderanch
Advance search
Google search
Register / Login
Dang Duy Hoang
Greenhorn
+ Follow
1
Posts
1
Threads
0
Cows
since Nov 17, 2016
Merit badge:
grant badges
For More
Cows and Likes
Cows
Total received
0
In last 30 days
0
Total given
0
Likes
Total received
0
Received in last 30 days
0
Total given
0
Given in last 30 days
0
Forums and Threads
Scavenger Hunt
Ranch Hand Scavenger Hunt
Number Posts (1/100)
Number Threads Started (1/100)
Number Cows Received (0/5)
Number Likes Received (0/10)
Number Likes Granted (0/20)
Set bumper stickers in profile (0/3)
Report a post to the moderators (0/1)
Edit a wiki page (0/1)
Create a post with an image (0/2)
Greenhorn Scavenger Hunt
First Post
Number Posts (1/10)
Number Threads Started (1/10)
Number Likes Received (0/3)
Number Likes Granted (0/3)
Set bumper stickers in profile (0/1)
Set signature in profile
Search for a post/thread (0/3)
Set a watch on a thread
Save thread as a bookmark
Create a post with an image (0/1)
Recent posts by Dang Duy Hoang
Get value in map by key is object class
I am reading "Item 9: Always override hashCode when you override equals" in Effective Java book.
I creat entity Person:
private String name; private int age; // getter and setter @Override public int hashCode() { int result = hashCode; if (result == 0) { result = 17; result = 31 * result + name.hashCode(); result = 31 * result + age; hashCode = result; } return result; } @Override public boolean equals(Object obj) { if (this == obj) return true; if (obj == null) return false; if (getClass() != obj.getClass()) return false; Person other = (Person) obj; if (age != other.age) return false; if (name == null) { if (other.name != null) return false; } else if (!name.equals(other.name)) return false; return true; }
class Main have:
Map<Person, String> map = new HashMap<Person, String>(); Person person = new Person("hoang", 21); map.put(person, "ifi"); System.out.println(person.hashCode()); map.get(person);
My problem that can't get object so I put into map before.
Could anybody help me to solve.
Thanks!
show more
7 years ago
Beginning Java