Java: How to check if a string is a part of any LinkedList element?

问题

Okay so I have a LinkedList, and I have a String. I want to check if the String is contained within any of the LinkedList elements. For example:

String a = "apple";
String listelement = "a bunch of apples";
LinkedList list = new LinkedList();
list.add(listelement);
if(list.containsany(a){
   System.out.println("Hooray!");
}

Would result in printing "Hooray!"

Obviously list.containsany isn't a real LinkedList method, I'm just using it for this purpose.

So how can I simulate my example?

Thanks

回答1:

String a = "apple";
String listelement = "a bunch of apples";
List<String> list = new LinkedList<String>();
list.add(listelement);
for(String s : list){
  if(s.contains(a)){
   syso("yes");
  }
}

This should do it, in order to find a node contains a particular string, you need to iterate through all the nodes. You can break the loop, if you want only 1 instance.

Also you want to use Generics. Look at the code. otherwise you will have to cast the node to a String.

回答2:

String a = "apple";
    String listelement = "a bunch of apples";
    LinkedList<String> list = new LinkedList<String>();
    list.add(listelement);
    Iterator<String> li = list.iterator();
    while (li.hasNext()) {
        if (li.next().contains(a)) {
            System.out.println("Hooray!");
        } 
    }

回答3:

linkedlist has a contains method in it.

http://download.oracle.com/javase/1.4.2/docs/api/java/util/LinkedList.html#contains(java.lang.Object)

回答4:

You would have to iterate across the list, and check each node's value to see if it was a string. If you can guarantee that all members of the linked list should be strings, using Java's Generics to force them all to be Strings may help.

     /*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package javaapplication1;

import java.util.LinkedList;

public class JavaApplication1 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        String a = "apple";
        String listelement = "a bunch of apples";
        LinkedList<String> list = new LinkedList<String>();
        list.add(listelement);
        list.add(new String("boogie"));
        for (String s : list) {
            if (s.contains(a)) {
                System.out.println("yes," + s + " contains " + a);
            } else {
                System.out.println("no," + s + " does not contain " + a);
            }
        }
    }
}

来源：https://stackoverflow.com/questions/7829034/java-how-to-check-if-a-string-is-a-part-of-any-linkedlist-element

标签

java

string

linked-list

contain