copyingarrays.java

Java编程思想 第九课 全源码

//: c09:CopyingArrays.java
// From 'Thinking in Java, 2nd ed.' by Bruce Eckel
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
// Using System.arraycopy()
import com.bruceeckel.util.*;
import java.util.*;

public class CopyingArrays {
  public static void main(String[] args) {
    int size = 15;
    if(args.length != 0)
    	size = Integer.parseInt(args[0]);
    int[] i = new int[size];
    int[] j = new int[size];
    Arrays.fill(i, 47);
    Arrays.fill(j, 99);
    Arrays2.print("i = ", i);
    Arrays2.print("j = ", j);
    System.arraycopy(i, 0, j, 0, i.length);
    Arrays2.print("j = ", j);
    int[] k = new int[10];
    Arrays.fill(k, 103);
    System.arraycopy(i, 0, k, 0, k.length);
    Arrays2.print("k = ", k);
    Arrays.fill(k, 103);
    System.arraycopy(k, 0, i, 0, k.length);
    Arrays2.print("i = ", i);
    // Objects:
    Integer[] u = new Integer[10];
    Integer[] v = new Integer[5];
    Arrays.fill(u, new Integer(47));
    Arrays.fill(v, new Integer(99));
    Arrays2.print("u = ", u);
    Arrays2.print("v = ", v);
    System.arraycopy(v, 0, 
      u, u.length/2, v.length);
    Arrays2.print("u = ", u);
  }
} ///:~