checkversion.java

luajava应用

//: com:bruceeckel:tools:CheckVersion.java
// {RunByHand}
package com.bruceeckel.tools;

public class CheckVersion {
  public static void main(String[] args){
    String version = System.getProperty("java.version");
    char minor = version.charAt(2);
    if (minor < '4')
      throw new RuntimeException("JDK 1.4.0 or higher " +
        "is required to run the examples in this book.");
    System.out.println("JDK version checked out.");
  }
} ///:~