list 群体.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

015:   }
016:  }
017: 
018:  public static void main(String args[]) {
019: // Construct the container
020:   ArrayList charts = new ArrayList();
021: 
022: // Insert some Data objects
023:   charts.add(new Chart(11013, "Morehead City Hrbr ", 12500));
024:   charts.add(new Chart(11552, "Neuse River        ", 40000));
025:   charts.add(new Chart(11428, "Dry Tortugas       ", 30000));
026:   charts.add(new Chart(11420, "Havana to Tampa Bay", 470940));
027:   charts.add(new Chart(25641, "Virgin Islands     ", 100000));
028:   charts.add(new Chart(26341, "Bermuda Islands    ", 50000));
029: 
030:   System.out.println("/nCharts shown by an Iterator object");
031:   showContainer(charts);
032: 
033:   // Erase first object
034:   Iterator I = charts.iterator();  // Get an Iterator object
035:   if (I.hasNext()) {               // Always call hasNext() and
036:    Chart c = (Chart)I.next();      //  next() before 
037:    I.remove();                     //  calling remove()
038:   }
039:   System.out.println("/nAfter removing first object");
040:   showContainer(charts);
041: 
042:   // Use Iterator to remove all objects
043:   I = charts.iterator();  // Get a fresh Iterator
044:   while (I.hasNext()) {
045:    I.next();    // Don't need to save returned object
046:    I.remove();  // Removes object last returned by next()
047:   }
048:   System.out.println("/nAfter removing all objects");
049:   System.out.println("Container size = " + charts.size());
050:  }
051: }

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List 群体 List.10 LinkedListDemo/LinkedListDemo.java 
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001: import java.util.List;
002: import java.util.LinkedList;
003: import java.util.ListIterator;
004: import java.util.Collections;
005: import Chart;
006: 
007: class LinkedListDemo {
008: 
009:  static final boolean FORWARD = true;
010:  static final boolean REVERSE = false;
011: 
012: // Display a LinkedList using a ListIterator
013: //  in forward or reverse order
014:  public static void showContainer(List c, boolean forward) {
015:   Chart achart;
016:   if (forward) {
017:    // Show in forward order
018:    ListIterator I = c.listIterator();
019:    while (I.hasNext()) {
020:     achart = (Chart)I.next();
021:     System.out.println(achart.toString());
022:    }
023:   } else {
024:    // Show in reverse order
025:    ListIterator I = c.listIterator(c.size());
026:    while (I.hasPrevious()) {
027:     achart = (Chart)I.previous();
028:     System.out.println(achart.toString());
029:    }
030:   }
031:  }
032: 
033:  public static void main(String args[]) {
034: // Construct the container
035:   LinkedList charts = new LinkedList();  // Can't specify size
036:   Chart achart;  // For accessing the container's objects
037: 
038: // Insert some Data objects
039:   charts.add(new Chart(11013, "Morehead City Hrbr ", 12500));
040:   charts.add(new Chart(11552, "Neuse River        ", 40000));
041:   charts.add(new Chart(11428, "Dry Tortugas       ", 30000));
042:   charts.add(new Chart(11420, "Havana to Tampa Bay", 470940));
043:   charts.add(new Chart(25641, "Virgin Islands     ", 100000));
044:   charts.add(new Chart(26341, "Bermuda Islands    ", 50000));
045: 
046:   // Sort the LinkedList container
047:   Collections.sort(charts);
048: 
049:   // Display head and tail objects
050:   System.out.println("/nHead object is:");
051:   achart = (Chart)charts.getFirst();
052:   System.out.println(achart.toString());
053:   System.out.println("/nTail object is:");
054:   achart = (Chart)charts.getLast();
055:   System.out.println(achart.toString());
056: 
057:   // Show list in forward and reverse order
058:   System.out.println("/nList in forward order");
059:   showContainer(charts, FORWARD);
060:   System.out.println("/nList in reverse order");
061:   showContainer(charts, REVERSE);
062:  }
063: }

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List 群体 List.11 ListIterator.txt 
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001: // Inherited Iterator methods
002: boolean hasNext();
003: Object next();
004: void remove();
005: // ListIterator interface methods
006: boolean hasPrevious();
007: Object previous();
008: int nextIndex();
009: int previousIndex();
010: void set(Object o);
011: void add(Object o);

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List 群体 List.12 BinaryDemo/BinaryDemo.java 
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001: import java.util.List;
002: import java.util.Comparator;
003: import java.util.ArrayList;
004: import java.util.Collections;
005: import Chart;
006: 
007: class BinaryDemo {
008: 
009:  // Display a List container's contents
010:  public static void showContainer(List c) {
011:   for (int i = 0; i < c.size(); i++)
012:    System.out.println(c.get(i).toString());
013:  }
014: 
015:  public static void main(String args[]) {
016: // Construct the container
017:   ArrayList charts = new ArrayList();
018: 
019: // Insert some Data objects
020:   charts.add(new Chart(11013, "Morehead City Hrbr ", 12500));
021:   charts.add(new Chart(11552, "Neuse River        ", 40000));
022:   charts.add(new Chart(11428, "Dry Tortugas       ", 30000));
023:   charts.add(new Chart(11420, "Havana to Tampa Bay", 470940));
024:   charts.add(new Chart(25641, "Virgin Islands     ", 100000));
025:   charts.add(new Chart(26341, "Bermuda Islands    ", 50000));
026: 
027: // Display all objects if none requested
028:   if (args.length == 0) {
029:    System.out.println("/nContainer contents:");
030:    showContainer(charts);
031:    System.out.println("/nEnter a chart number to find");
032:    System.out.println("ex. java BinaryDemo 11428");
033:   } else {
034: 
035: // Search container using Collections.binarySearch()
036:    try {
037: // Preparations for a binarySearch();
038:     int num = Integer.parseInt(args[0]); // Get chart number
039:     Comparator comp = Chart.byNumber();  // Create Comparator
040:     Chart key = new Chart(num, "", 0);   // Create search key 
041:     Collections.sort(charts, comp);      // Sort container
042: 
043: // Search the container for the key object
044:     int index = Collections.binarySearch(charts, key, comp);
045:     if (index < 0)
046:      System.out.println("Chart #" + args[0] + " not found");
047:     else
048:      System.out.println(charts.get(index)); // Show chart
049:    }
050:     catch (NumberFormatException e) {
051:     System.out.println("Error in argument " + e.getMessage());
052:    }
053:   }
054:  }
055: }

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List 群体 List.13 StackDemo/Stack.java 
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001: import java.util.Collection;
002: import java.util.LinkedList;
003: 
004: class StackEmptyException extends Exception {
005:  StackEmptyException(String s) { super(s); }
006: }
007: 
008: public class Stack extends LinkedList {
009: // Constructors
010:  public Stack() { super(); }
011:  public Stack(Collection c) { super(c); }
012: // Public methods
013:  public void push(Object o) {
014:   addLast(o);
015:  }
016:  public Object pop() throws StackEmptyException {
017:   if (size() == 0)
018:    throw new StackEmptyException("pop on empty stack");
019:   return removeLast();
020:  }
021:  public Object peek() throws StackEmptyException {
022:   if (size() == 0)
023:    throw new StackEmptyException("peek on empty stack");
024:   return getLast();
025:  }
026: // Unsupported methods (incomplete -- see text)
027:  public final Object removeFirst() {
028:   throw new UnsupportedOperationException();
029:  } 
030:  public final void addFirst(Object o) {
031:   throw new UnsupportedOperationException();
032:  } 
033: }

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List 群体 List.14 StackDemo/StackDemo.java 
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001: import Stack;
002:  
003: class StackDemo {
004:  public static void main(String args[]) {
005:   String s;
006:   try {
007:    Stack fruitStack = new Stack();
008:    fruitStack.push("Apples");
009:    fruitStack.push("Peaches");
010:    fruitStack.push("Pumpkin");
011: // Enable following to force an unchecked exception
012: //   fruitStack.removeFirst();
013: // Peek at top of stack 
014:    s = (String)fruitStack.peek();
015:    System.out.println("/nTop of stack = " + s);  
016: // Pop all objects from stack
017:    System.out.println("/nPopping all objects:");
018:    while (!fruitStack.isEmpty()) {
019:     s = (String)fruitStack.pop();
020:     System.out.println(s);
021:    }
022: // Enable following to force a checked exception
023: //   s = (String)fruitStack.pop();
024:   } catch (StackEmptyException e) {
025:    System.out.println("*** Error: " + e.getMessage());
026:   }
027:  }
028: }

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