この最初の部分は、Web から見つけた例を変更して、さまざまなソリューションをすばやく試すことができます。タイトルにあるように、WordHold オブジェクトを取得する必要があるときに引き続き変更できるように、WordHold オブジェクトを取得する方法がわかりません。
import java.util.Collection;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Set;
public class HashtableDemo {
public static void main(String args[]) {
WordHold temp = new WordHold("test1", "test2");
WordHold temp2;
// Creating Hashtable for example
Hashtable companies = new Hashtable();
// Java Hashtable example to put object into Hashtable
// put(key, value) is used to insert object into map
companies.put("Google", temp);
companies.put("Nokia", "Finland");
companies.put("Sony", "Japan");
// Java Hashtable example to get Object from Hashtable
// get(key) method is used to retrieve Objects from Hashtable
temp2 = companies.get("Google");
// Hashtable containsKey Example
// Use containsKey(Object) method to check if an Object exits as key in
// hashtable
System.out.println("Does hashtable contains Google as key: "
+ companies.containsKey("Google"));
// Hashtable containsValue Example
// just like containsKey(), containsValue returns true if hashtable
// contains specified object as value
System.out.println("Does hashtable contains Japan as value: "
+ companies.containsValue("Japan"));
// Hashtable enumeration Example
// hashtabl.elements() return enumeration of all hashtable values
Enumeration enumeration = companies.elements();
while (enumeration.hasMoreElements()) {
System.out
.println("hashtable values: " + enumeration.nextElement());
}
// How to check if Hashtable is empty in Java
// use isEmpty method of hashtable to check emptiness of hashtable in
// Java
System.out.println("Is companies hashtable empty: "
+ companies.isEmpty());
// How to find size of Hashtable in Java
// use hashtable.size() method to find size of hashtable in Java
System.out.println("Size of hashtable in Java: " + companies.size());
// How to get all values form hashtable in Java
// you can use keySet() method to get a Set of all the keys of hashtable
// in Java
Set hashtableKeys = companies.keySet();
// you can also get enumeration of all keys by using method keys()
Enumeration hashtableKeysEnum = companies.keys();
// How to get all keys from hashtable in Java
// There are two ways to get all values form hashtalbe first by using
// Enumeration and second getting values ad Collection
Enumeration hashtableValuesEnum = companies.elements();
Collection hashtableValues = companies.values();
// Hashtable clear example
// by using clear() we can reuse an existing hashtable, it clears all
// mappings.
companies.clear();
}
}
使用されているサブクラス。
public class WordHold
{
// instance variables - replace the example below with your own
private String wrongWord;
private String correctWord;
private WordHold next;
public WordHold(String wordWrong, String wordCorrect)
{
wrongWord = wordWrong;
correctWord = wordCorrect;
}
/**
* Returns the wrong word
*
* @return The stored wrong word.
*/
public String getWrongWord()
{
return wrongWord;
}
/**
* Returns the correct word
*
* @return The stored wrong word.
*/
public String getCorrectWord()
{
return correctWord;
}
/**
* Returns the next element
*
* @return The next element in list.
*/
public WordHold getNext()
{
return next;
}
/**
* Sets next element in the list.
*/
public WordHold setNext()
{
return next;
}
public String toString()
{
String temp = (wrongWord + " no " + correctWord);
return temp;
}
}