comparable interface

[JavaSE] Java generic mechanism, javasejava generic**************************************** ********************************* *** Original article: blog.csdn.net/clark_xu Xu changliang's column**************************************** ****************

Set for detailed collection, Hashset Unordered: the order in which elements are added is inconsistent with that in which elements are displayed. Hashset implementation principle: when adding an element to a hashset, hashset first calls the hashcode

First   Question: 1Given:11. public class Person {12. private String name, comment;13. private int age;14. public Person (String n, int a, String c ){15. name = n; age = a; comment = c;16 .}17. public boolean equals (Object o ){18. if (! (O

Sometimes you need to compare Collection objects or arrays that are not a single number. There are two methods: 1 is to implement the Comparable interface and 2 is to implement the Comparator interface. 1. the ComParable interface Comparable

In the observation of Java source code, the discovery of such a notation T extends comparable. Can't help wondering why it's written like this? What are the benefits, extends and super's role here is a bit unclear.Next, I'll share the code with you

1. The difference between array and other containers is that it can hold privitive objects with high efficiency. Try to use arrays first. Array copy system. arraycopy (). This copy is a shortest copy (that is, for the object array, it copies the

Reprint Please specify the Source: http://blog.csdn.net/ns_code/article/details/36421085PrefaceThis article does not intend to perpetuate the previous few styles (add gaze to all the source code), because to understand the full source of TreeMap.

What is a 1.Java set frame? What are some of the advantages of a collection framework?There are collections in each programming language, and the original Java version contains several collection classes: Vector, Stack, Hashtable, and array. With

1, comparable introduction comparable is a sort interface, if a class implements the interface, the class itself can be sorted . Note that in addition to the basic data type (eight basic data types) array or list, the remaining types of

There are two forms of using wildcard characters in generics: subtype-qualified and super Type limited .(1) Sub-type qualificationThe following code defines a pair class, as well as the Employee,manager and President classes.public class Pair

first, what is the difference between a collection and an array? 1. Length:The array is fixed, and the collection is mutable.2. Storage type:Arrays store basic data types and objects, and collections can store only basic data types.An array-stored

The difference between a set interface set type and a list type for a Java collection Set: Unordered, non-repeatable List: Ordered, repeatable 1, HASHSETHASHSET storage structure: HashMap Features: HashSet to determine

/*treeset* TreeSet automatically calls the element's CompareTo (Object obj) method after the data is stored and automatically sorts the data* So the output data is sorted data* Note: The return value of the CompareTo method is: Negative, 0, positive.

The set set is similar to a jar, thrown into "set", and there is no apparent order between objects in the collection.The set set is essentially the same as the collection collection, and he does not provide any additional methods.in fact set is

What is a 1.Java set frame? What are some of the advantages of a collection framework?There are collections in each programming language, and the original Java version contains several collection classes: Vector, Stack, Hashtable, and array. With

Collection The JDK class library provides a Java collection in which all Java collection classes are located in the Java.util package. Unlike Java arrays, basic type data cannot be stored in a Java collection, and only references to objects are

For set There are generally two ways to implement the sort function, where the basic type is not applicable, and the basic type generally has a static method in the arrays. 1. The object itself implements the comparable interface, so instances of

ordering an array of objects in JavaBy Icycandy, at 2009/03/06 09:43:00 In the Java sorting seems not so convenient in C + +, search for a long time to see a lot of articles, probably are said to use arrays or ArrayList or list or collection, etc.

use of template methods in the Java API 1.arrays.sort () sort When sorting arrays, we often use the Arrays.sort () method, and the sort () method of the Arrays class is the template method. The focus of the template method pattern is to provide

Recently watching video, see more classic than the size of the problem. Enter two numbers, return a large number, type can be int,long,float, etc.The general tutorial uses this example to introduce the concept of constructors and overloading, and