我有一个项目,我正在为我的Java类(显然)工作,我一定错过了关于如何与TreeMaps进行交互的讲座。我不知道我在做什么,并且我没有从Google获得很多帮助。如何打印TreeMap中的所有值?
对于程序中的第一种情况,我必须打印TreeMap的所有值。以下是我提供的代码以及我已完成的工作。情况A中的一切都是我的,但它不起作用。任何帮助,将不胜感激。
import java.util.Scanner;
import java.util.Set;
import java.util.Map;
import java.util.TreeMap;
import java.io.File;
import java.io.FileNotFoundException;
public class prog7 {
public static void main(String args[])
throws FileNotFoundException
{
Scanner kb=new Scanner(System.in);
/*here, add code to declare and create a tree map*/
TreeMap treeMap = new TreeMap();
/*here, add code to declare a variable and
let it be the key set of the map
*/
String key;
//temporary variables
String tempWord;
String tempDef;
//the following code reads data from the file glossary.txt
//and saves the data as entries in the map
Scanner infile=new Scanner(new File("glossary.txt"));
while(infile.hasNext())
{
tempWord=infile.nextLine();
tempDef=infile.nextLine();
/*here, add code to add tempWord and tempDef
as an entry in the map
*/
treeMap.put(tempWord, tempDef);
}
infile.close();
while(true)
{
System.out.println();
System.out.println();
//show menu and prompt message
System.out.println("Please select one of the following actions:");
System.out.println("q - Quit");
System.out.println("a - List all words and their definitons");
System.out.println("b - Enter a word to find its definition");
System.out.println("c - Add a new entry");
System.out.println("d - Delete an entry");
System.out.println("Please enter q, a, b, c or d:");
String selection=kb.nextLine(); //read user's selection
if (selection.equals("")) continue; //if selection is "", show menu again
switch (selection.charAt(0))
{
case 'q':
System.out.println("\nThank you.");
return;
/*write code for the cases 'a','b','c' and 'd'
so that the program runs as in the sample run
*/
case 'a':
for (String treeKey : treeMap.keySet())
System.out.println(treeKey);
break;
+1使用功课标签和张贴你到目前为止的代码。 – 2011-04-22 15:53:46