我正在尝试编写一些代码，该代码使用扫描器输入来询问LibraryPatron的名称，并使用contains（）方法来检查LibraryPatron是否在列表中。我没有关于contains（）方法如何工作的问题，而是关于如何使用它来检查对象名称的问题。预先感谢。
这是我的LinkedList类（在本例中为BagList），已经有一个contains（）方法：
package libraryPatrons;
public final class BagList<T> implements BagInterface<T> {
Node firstNode;
int numPatrons;
public BagList() {
firstNode = null;
numPatrons = 0;
}
public int getCurrentSize() {
return numPatrons;
}
/** Sees whether this bag is empty.
* @return True if the bag is empty, or false if not. */
public boolean isEmpty() {
return firstNode == null;
}
/** Adds a new entry to this bag.
* @param newEntry The object to be added as a new entry.
* @return True if the addition is successful, or false if not. */
public boolean add(T newEntry) {
Node newNode = new Node (newEntry);
newNode.next = firstNode;
firstNode = newNode;
++numPatrons;
return true;
}
/** Removes one unspecified entry from this bag, if possible.
* @return The removed entry if the removal was successful, or null. */
public T remove() {
T result = null;
if (firstNode != null) {
result = firstNode.data;
firstNode = firstNode.next;
--numPatrons;
}
return result;
}
private Node getReferenceTo (T anEntry) {
Node currentNode = firstNode;
boolean found = false;
while (!found && currentNode != null) {
if (anEntry.equals(currentNode.data)) {
found = true;
} else {
currentNode = currentNode.next;
}
}
return currentNode;
}
/** Removes one occurrence of a given entry from this bag.
* @param anEntry The entry to be removed.
* @return True if the removal was successful, or false if not. */
public boolean remove(T anEntry) {
boolean result = false;
Node currentNode = getReferenceTo (anEntry);
if (currentNode != null) {
currentNode.data = firstNode.data;
firstNode = firstNode.next;
--numPatrons;
result = true;
}
return result;
}
/** Removes all entries from this bag. */
public void clear() {
while (!isEmpty()) {
remove();
}
numPatrons = 0;
}
/** Counts the number of times a given entry appears in this bag.
* @param anEntry The entry to be counted.
* @return The number of times anEntry appears in the bag. */
public int getFrequencyOf(T anEntry) {
Node currentNode = firstNode;
int frequency = 0;
while (currentNode != null) {
if (anEntry.equals(currentNode.data))
++frequency;
currentNode = currentNode.next;
}
return frequency;
}
/** Tests whether this bag contains a given entry.
* @param anEntry The entry to locate.
* @return True if the bag contains anEntry, or false if not. */
public boolean contains(T anEntry) {
Node currentNode = getReferenceTo (anEntry);
return !(currentNode == null);
}
/** Retrieves all entries that are in this bag.
* @return A newly allocated array of all the entries in the bag.
* Note: If the bag is empty, the returned array is empty. */
public T[] toArray() {
T[] newArray = (T[]) new Object[numPatrons];
int index = 0;
Node currentNode = firstNode;
while (currentNode != null) {
newArray[index] = currentNode.data;
++index;
currentNode = currentNode.next;
}
return newArray;
}
private class Node {
private T data;
private Node next;
private Node (T dataPortion) {
this(dataPortion, null);
}
private Node (T dataPortion, Node nextNode) {
this.data = dataPortion;
this.next = nextNode;
}
}
}
这是我的主班：
package libraryPatrons;
import java.util.Scanner;
class Main {
public static void main (String args[]) {
LibraryPatron patron1 = new LibraryPatron("Bob", "3814872910", "Adelaide Way", "Belmont", "94002");
LibraryPatron patron2 = new LibraryPatron("Les", "3860165016", "Chevy St", "Belmont", "94002");
LibraryPatron patron3 = new LibraryPatron("Anna", "7926391055", "Davey Glen Rd", "Belmont", "94002");
LibraryPatron patron4 = new LibraryPatron("Amy", "7619356016", "Fernwood Way", "Belmont", "94002");
LibraryPatron patron5 = new LibraryPatron("Tom", "1758563947", "Flasner Ln", "Belmont", "94002");
LibraryPatron patron6 = new LibraryPatron("James", "4729573658", "Marsten Ave", "Belmont", "94002");
LibraryPatron patron7 = new LibraryPatron("Jason", "3858239773", "Middlesex Rd", "Belmont", "94002");
LibraryPatron patron8 = new LibraryPatron("Jess", "3866392656", "Oxford Ct", "Belmont", "94002");
LibraryPatron patron9 = new LibraryPatron("Mike", "7836591904", "Sem Ln", "Belmont", "94002");
LibraryPatron patron10 = new LibraryPatron("Abby", "1960265836", "Tioga Way", "Belmont", "94002");
LibraryPatron patron11 = new LibraryPatron("Dom", "5917485910", "Village Dr", "Belmont", "94002");
LibraryPatron patron12 = new LibraryPatron("Wes", "5810385736", "Willow Ln", "Belmont", "94002");
BagList<LibraryPatron> listOfPatrons = new BagList<LibraryPatron>();
listOfPatrons.add(patron1);
listOfPatrons.add(patron2);
listOfPatrons.add(patron3);
listOfPatrons.add(patron4);
listOfPatrons.add(patron5);
listOfPatrons.add(patron6);
listOfPatrons.add(patron7);
listOfPatrons.add(patron8);
listOfPatrons.add(patron9);
listOfPatrons.add(patron10);
listOfPatrons.add(patron11);
listOfPatrons.add(patron12);
Scanner patronInput = new Scanner(System.in);
String name = patronInput.nextLine();
System.out.println("Does this list of library patrons contain: " + name + "?");
System.out.println(/* contains(objectName)? */);
}
}
在main（）函数中，我想询问LibraryPatron的名称，并使用contains（）方法来检查LibraryPatron是否在列表中。