randombounds.java

来自「中文JAVA编程思想第二版,一本很好的JAVA入门书籍!」· Java 代码 · 共 28 行

//: c03:RandomBounds.java
// From 'Thinking in Java, 2nd ed.' by Bruce Eckel
// www.BruceEckel.com. See copyright notice in CopyRight.txt.
// Does Math.random() produce 0.0 and 1.0?

public class RandomBounds {
  static void usage() {
    System.out.println("Usage: \n\t" +
      "RandomBounds lower\n\t" +
      "RandomBounds upper");
    System.exit(1);
  }
  public static void main(String[] args) {
    if(args.length != 1) usage();
    if(args[0].equals("lower")) {
      while(Math.random() != 0.0)
        ; // Keep trying
      System.out.println("Produced 0.0!");
    } 
    else if(args[0].equals("upper")) {
      while(Math.random() != 1.0)
        ; // Keep trying
      System.out.println("Produced 1.0!");
    } 
    else 
      usage();
  }
} ///:~