java例程练习（Comparable接口）

import java.lang.Comparable; import java.util.List; import java.util.LinkedList; import java.util.Collections; public class TestCompareTo { public static void main(String[] args) { List l1 = new LinkedList(); l1.add(new Name("Karl", "M")); l1.add(new Name("Stever", "Lee")); l1.add(new Name("John", "O")); l1.add(new Name("Tom", "M")); System.out.println(l1); Collections.sort(l1); System.out.println(l1); } } class Name implements Comparable{ private String firstName; private String lastName; Name(String firstName, String lastName) { this.setFirstName(firstName); this.setLastName(lastName); } public void setFirstName(String firstName) { this.firstName = firstName; } public String getFirstName() { return firstName; } public void setLastName(String lastName) { this.lastName = lastName; } public String getLastName() { return lastName; } public String toString() { return firstName + " " + lastName; } public boolean equals(Object obj) { if(obj instanceof Name) { Name name = (Name) obj; return (firstName.equals(name.firstName)) && (lastName.equals(name.lastName)); } return super.equals(obj); } public int hashCode() { return firstName.hashCode(); } public int compareTo(Object o) { Name n = (Name) o; int lastCmp = lastName.compareTo(n.lastName); return (lastCmp != 0 ? lastCmp : firstName.compareTo(n.firstName)); } }