Testing - Max's Book

[Mike Yu]

Hi Max,
In your book, there is a test package. I don't quite understand some code in DBTestRunner.java, that is,
while (test1.isAlive()
&& test2.isAlive()
&& test3.isAlive()
&& test4.isAlive()
&& test5.isAlive()
&& test1.isAlive()) {
}
System.out.println("Completed all tests.");
This means that if one thread is dead, then the test is completed. Why?
As I imagine, if the test is completed, then all thread should be dead. Can you explain?

[Max Habibi]

HI Mike,
I don't have the book handy. Can you give me a little more context?
M

[Mike Yu]

Hi Max,
The following is the full code:

package sampleproject.test;
import sampleproject.db.*;
//Uncomment the DVDConnector of the protocol you want to use.
import sampleproject.remote.DVDConnector;
//import sampleproject.sockets.DVDConnector;
public class DBTester extends Thread{
    public static final int TYPE_RETURN = 1;
    public static final int TYPE_RENT = 2;
    private String title;
    private int hitCount;
    private String recordNumber;
    private sampleproject.db.DBClient db;
    private int type;
    public DBTester() {
    }
    public DBTester(String title, int hitCount, String recordNumber, int type) {
        this();
try {
        db = DVDConnector.getRemote("localhost");
} catch(Exception e) {}
        this.title = title;
        this.hitCount = hitCount;
        this.recordNumber = recordNumber;
        this.db = db;
        this.type = type;
        super.setName(this.title);
    }
    public void run(){
        for (int i = 0; i < this.hitCount; i++){
             try{
                this.setName(this.title + " hit count = " + i);
                switch (this.type){
                    case (TYPE_RETURN):
                        db.returnRental(this.recordNumber);
                        break;
                    case (TYPE_RENT):
                        db.rent(this.recordNumber);
                        break;
                    default:
                        db.returnRental(this.recordNumber);
                        break;
                }
            }
            catch (Exception e){
                System.err.println(e.getMessage());
                e.printStackTrace(System.err);
            }
        }
    }
    public void setTitle(String title) {
        this.title = title;
    }
    public String getTitle() {
        return title;
    }
    public String toString (){
        return "My name is " + this.title;
    }
    public void setHitCount(int hitCount) {
        this.hitCount = hitCount;
    }
    public int getHitCount() {
        return hitCount;
    }
    public void setRecordNumber(String recordNumber) {
        this.recordNumber = recordNumber;
    }
    public String getRecordNumber() {
        return recordNumber;
    }
    public void setDb(sampleproject.db.DBClient db) {
        this.db = db;
    }
    public sampleproject.db.DBClient getDb() {
        return db;
    }
    public void setType(int type) {
        this.type = type;
    }
    public int getType() {
        return type;
    }
}
******************************
package sampleproject.test;
import sampleproject.db.*;
public class DBTestRunner {
    public static void main(String[] args) {
        DBTestRunner DBTestRunner1 = new DBTestRunner();
    }
    public DBTestRunner() {
        DBTester test1 = new DBTester ("----Returner----", 2, "85392246724",
                                                        DBTester.TYPE_RETURN);
        DBTester test2 = new DBTester ("----Returner----", 2, "85392246724",
                                                        DBTester.TYPE_RETURN);
        DBTester test3 = new DBTester ("----Returner----", 2, "85392246724",
                                                        DBTester.TYPE_RETURN);
        DBTester test4 = new DBTester ("----Returner----", 2, "85392246724",
                                                        DBTester.TYPE_RETURN);
        DBTester test5 = new DBTester ("----Renter----", 5, "85392246724",
                                                        DBTester.TYPE_RENT);
        DBTester test6 = new DBTester ("----Returner----", 2, "85392246724",
                                                        DBTester.TYPE_RETURN);
        test1.start();
        test2.start();
        test3.start();
        test4.start();
        test5.start();
        test6.start();
        while (test1.isAlive()
                && test2.isAlive()
                && test3.isAlive()
                && test4.isAlive()
                && test5.isAlive()
                && test1.isAlive())  {
        }
        System.out.println("Completed all tests.");
    }
}

[Andrew: I have put the code in between a UBB [code] and [/code] tags. This ensures that indenting is preserved, and makes the code easier to read. If you edit this post, you will see what I have done.]
[ September 16, 2003: Message edited by: Andrew Monkhouse ]

[Jim Yingst]

Good point, this seems to be a bug. I'd suggest replacing the while loop with:
test1.join();
test2.join();
test3.join();
test4.join();
test5.join();
test6.join();
This could at least be done in the downloadable verion of the code, right? The code is also listed on p. 333; guess that need to be in the errata.

[Jim Yingst]

Bump.

[Andrew Monkhouse]

Bump again