抽象类.txt

适合初学者练习 包括awt小程序、list和map群体等100多个java程序

抽象类 List.1 DataHiding/DataHiding.java 
抽象类 List.2 ProtectedData/ProtectedData.java 
抽象类 List.3 AbstractDemo/TObject.java 
抽象类 List.4 AbstractDemo/TContainer.java 
抽象类 List.5 AbstractDemo/TMyObject.java 
抽象类 List.6 AbstractDemo/AbstractDemo.java 

--------------------------------------------------------------------------------

抽象类 List.1 DataHiding/DataHiding.java 
Return to top 
001: class TDate {
002:  private int month, day, year;
003:  public TDate(int month, int day, int year) {
004:   setDate(month, day, year);
005:  }
006:  public void setDate(int month, int day, int year) {
007:   this.month = month;
008:   this.day = day;
009:   this.year = year;
010:  }
011:  public String getDate() {
012:   return month + "/" + day + "/" + year;
013:  }
014: }
015: 
016: class DataHiding {
017:  public static void main(String args[]) {
018:   TDate birthday = new TDate(8, 15, 1975);
019:   String s = birthday.getDate();
020:   System.out.println("birthday = " + s);
021:  }
022: }

Return to top 
--------------------------------------------------------------------------------

抽象类 List.2 ProtectedData/ProtectedData.java 
Return to top 
001: class TDate {
002:  protected int month, day, year;
003:  public TDate(int month, int day, int year) {
004:   setDate(month, day, year);
005:  }
006:  public void setDate(int month, int day, int year) {
007:   this.month = month;
008:   this.day = day;
009:   this.year = year;
010:  }
011:  public String getDate() {
012:   return month + "/" + day + "/" + year;
013:  }
014: }
015: 
016: class TDateTime extends TDate {
017:  protected int hour, min;
018:  public TDateTime(int month, int day, int year, 
019:   int hour, int min) {
020:   super(month, day, year);  // Call superclass constructor
021:   this.hour = hour;
022:   this.min = min;
023:  }
024:  public String getDate() {  // Override method
025:   return month + "/" + day + "/" + year +
026:    " : " + hour + ":" + min;
027:  }
028: }
029: 
030: class ProtectedData {
031:  public static void main(String args[]) {
032:   TDate now = new TDateTime(3, 15, 2001, 14, 45);
033:   String s = now.getDate();
034:   System.out.println("now = " + s);
035:  }
036: }

Return to top 
--------------------------------------------------------------------------------

抽象类 List.3 AbstractDemo/TObject.java 
Return to top 
001: abstract class TObject implements Comparable {
002:  abstract public int compareTo(Object other);
003:  abstract public void show();
004: }

Return to top 
--------------------------------------------------------------------------------

抽象类 List.4 AbstractDemo/TContainer.java 
Return to top 
001: import TObject;
002: import java.util.Arrays;
003: 
004: class ContainerFullException extends Exception { };
005: 
006: class TContainer {
007: // Private instance variables
008:  private int size;    // Size of objArray
009:  private int count;   // Count of objects in objArray
010:  private TObject objArray[];  // Array of objects
011: 
012: // Constructor (n = array size)
013:  public TContainer(int n) {
014:   if (n <= 0) n = 1;  // Minimum allowed size
015:   size = n;
016:   count = 0;
017:   objArray = new TObject[size];
018:  }
019: 
020: // Insert object into container
021:  public void putObject(TObject obj) 
022:   throws ContainerFullException {
023:   if (count >= size) 
024:    throw new ContainerFullException();
025:   objArray[count++] = obj;
026:  }
027: 
028: // Display all objects in container
029:  public void showAllObjects(String label) {
030:   System.out.println(label);
031:   for (int i = 0; i < count; i++)
032:    objArray[i].show();
033:   System.out.println();
034:  }
035: 
036: // Sort the objects in the container
037:  public void sort() {
038:   if (count > 1)
039:    Arrays.sort(objArray, 0, count);
040:  }
041: }

Return to top 
--------------------------------------------------------------------------------

抽象类 List.5 AbstractDemo/TMyObject.java 
Return to top 
001: import TObject;
002: 
003: class TMyObject extends TObject {
004:  private String s;
005: 
006: // Constructor
007:  TMyObject(String s) {
008:   this.s = s;
009:  }
010: 
011: // Implement Comparable interface method
012:  public int compareTo(Object other) {
013:   TMyObject otherObject = (TMyObject)other;
014:   return s.compareTo(otherObject.s);
015:  }
016: 
017: // Implement TObject abstract method
018:  public void show() {
019:   System.out.print(s + "  ");
020:  }
021: }

Return to top 
--------------------------------------------------------------------------------

抽象类 List.6 AbstractDemo/AbstractDemo.java 
Return to top 
001: import TContainer;
002: import TMyObject;
003: 
004: class AbstractDemo {
005:  public static void main(String args[]) {
006:   TContainer container = new TContainer(100);
007:   try {
008:    container.putObject(new TMyObject("Peach"));
009:    container.putObject(new TMyObject("Mango"));
010:    container.putObject(new TMyObject("Lime"));
011:    container.putObject(new TMyObject("Banana"));
012:    container.putObject(new TMyObject("Kiwi"));
013:    container.putObject(new TMyObject("Grapefruit"));
014:    container.putObject(new TMyObject("Orange"));
015:    container.putObject(new TMyObject("Lemon"));
016:    container.putObject(new TMyObject("Apple"));
017:    container.showAllObjects("Before sorting");
018:    container.sort();
019:    container.showAllObjects("After sorting");
020:   } catch (ContainerFullException e) {
021:    System.out.println("Container overflow error");
022:   }
023:  }
024: }

Return to top 
? 2003 by ChinaITLab.com All rights reserved.