varargstester.java

Java5.0 Tiger 程序员高手秘笈一书的源代码

package com.oreilly.tiger.ch05;

import java.io.IOException;
import java.io.PrintStream;
import java.util.LinkedList;
import java.util.List;

public class VarargsTester {

  public VarargsTester() {
  }

  private int[] getListOfNumbers() {
    int[] numbers = new int[] {0, 2, 4, 6, 8, 10, 9, 7, 5, 3, 1};
    return numbers;
  }

  private String print(Object... values) {
    StringBuilder sb = new StringBuilder();
    for (Object o : values) {
      sb.append(o.toString())
        .append(" ");
    }
    return sb.toString();
  }

  public void testMaxMethod(PrintStream out) throws IOException {
    int[] numbers = getListOfNumbers();

    int max = MathUtils.max(numbers);
    out.println("Max of list is: " + max);
  }

  public void testPrintMethod(PrintStream out) throws IOException {
    out.println(print("foo", 23, -12, 1.23, getListOfNumbers()));
  }

  public void testArrayArgs(PrintStream out) throws IOException {
    Object[] obj = new String[] {"Hello", "to", "all", "of", "you"};

    out.printf("%s\n", obj);
    out.printf("%s\n", (Object)obj);
  }

  public static void main(String[] args) {
    try {
      VarargsTester tester = new VarargsTester();

      tester.testMaxMethod(System.out);
      tester.testPrintMethod(System.out);
      tester.testArrayArgs(System.out);
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}