哈希表类rehash()方法 (Hashtable Class rehash() method)

• rehash() method is available in java.util package.

  rehash()方法在java.util包中可用。

• rehash() method is used to extend the capacity and it is invoked implicitly if the number of keys limit exceeds hashtable capacity.

  rehash()方法用于扩展容量，如果键数限制超过哈希表容量，则会隐式调用该方法。

• rehash() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  rehash()方法是一种非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。

• rehash() method does not throw an exception at the time of extending capacity.

  rehash()方法在扩展容量时不会引发异常。

Syntax:

句法：

    public void rehash();

Parameter(s):

参数：

• It does not accept any parameter.

  它不接受任何参数。

Return value:

返回值：

The return type of the method is void, it returns nothing.

该方法的返回类型为void ，不返回任何内容。

Example:

例：

// Java program to demonstrate the example
// of void rehash() method of Hashtable
import java.util.*;
public class RehashOfHashtable extends Hashtable {public static void main(String[] args) {//Instantiate a hashtable object
RehashOfHashtable ht = new RehashOfHashtable();
// By using put() method is to
// add the linked values in an
// Hashtable ht
ht.put(10, "C");
ht.put(20, "C++");
ht.put(30, "JAVA");
ht.put(40, "PHP");
ht.put(50, "SFDC");
// Display Hashtable
System.out.println("Hashtable: " + ht);
// By using rehash() method is to increase
// the capacity and re-organizes internally
// this Hashtable
ht.rehash();
System.out.println("ht.size(): " + ht.size());
}
}

Output

输出量

Hashtable: {10=C, 20=C++, 30=JAVA, 40=PHP, 50=SFDC}
ht.size(): 5

翻译自: https://www.includehelp.com/java/hashtable-rehash-method-with-example.aspx