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Arming ourselves to the teeth!

Java Multithreading, Level 5, Lesson 9

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Create your own UncaughtExceptionHandler as a local class inside the constructor.
The UncaughtExceptionHandler should hide the thread name with asterisks and display a description of the error that occurred.
"Thread-0" must be replaced with "********".
"Thread-4321" must be replaced with "***********".

Requirements:

Don't change the Solution class's definition or fields.
The Solution constructor must create its own UncaughtExceptionHandler, and store it in the handler field.
The created UncaughtExceptionHandler should display a description of the error that occurred.
In the error description, the thread name should be hidden by "*" characters.

package com.codegym.task.task25.task2511; import java.util.TimerTask; /* Arming ourselves to the teeth! */ public class Solution extends TimerTask { protected TimerTask original; protected final Thread.UncaughtExceptionHandler handler; public Solution(TimerTask original) { if (original == null) { throw new NullPointerException(); } this.original = original; this.handler = null;// Init handler here Thread thread = new Thread(); thread.setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() { @Override public void uncaughtException(Thread t, Throwable e) { } }); } public void run() { try { original.run(); } catch (Throwable cause) { Thread currentThread = Thread.currentThread(); handler.uncaughtException(currentThread, new Exception("Blah " + currentThread.getName() + " blah-blah-blah", cause)); } } public long scheduledExecutionTime() { return original.scheduledExecutionTime(); } public boolean cancel() { return original.cancel(); } public static void main(String[] args) { } }

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Djole

Level 41 , Belgrade, Serbia

16 June 2019, 10:16

instead of this.handler = null; use this.handler = new Thread.UncaughtExceptionHandler() { }; in order to create UncaughtExceptionHandler local class. in uncaughtException(Thread t, Throwable e) e.getMessage() gives you description of error. t.getName().replaceAll(".", "*"); will hide the name with stars. combine all that in your print statement.

Satya Vath

Level 31 , Vijayawada, India

16 June 2019, 11:15

Still Not Verifying Help

package com.codegym.task.task25.task2511;

import java.util.*;

/*
Arming ourselves to the teeth!

*/
public class Solution extends TimerTask {
    protected TimerTask original;
    protected final Thread.UncaughtExceptionHandler handler;

    public Solution(TimerTask original) {
        if (original == null) {
            throw new NullPointerException();
        }
        this.original = original;
        this.handler = new Thread.UncaughtExceptionHandler()
        {
            @Override
            public void uncaughtException(Thread t, Throwable e)
            {
                System.out.println(e.getMessage());
                System.out.println(t.getName().replaceAll(".", "*"));

            }
        };
        Thread thread = new Thread();
        thread.setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler()
        {
            @Override
            public void uncaughtException(Thread t, Throwable e)
            {

            }
        });

    }

    public void run() {
        try {
            original.run();
        } catch (Throwable cause) {
            Thread currentThread = Thread.currentThread();
            handler.uncaughtException(currentThread, new Exception("Blah " + currentThread.getName() + " blah-blah-blah", cause));
        }
    }

    public long scheduledExecutionTime() {
        return original.scheduledExecutionTime();
    }

    public boolean cancel() {
        return original.cancel();
    }

    public static void main(String[] args) {
    }
}

Djole

Level 41 , Belgrade, Serbia

16 June 2019, 11:57

what do you need lines 28-35 for? also, this is not what is asked for. System.out.println(e.getMessage()); System.out.println(t.getName().replaceAll(".", "*")); this will display two lines. one line will print error description, the other will print stars, but this is the requirement: 'In the error description, the thread name should be hidden by "*" characters.' you need to combine those two into single print, possibly with another replaceAll() to get the desired display.

Satya Vath

Level 31 , Vijayawada, India

16 June 2019, 12:17

Still Cant Verify

package com.codegym.task.task25.task2511;

import java.util.*;

/*
Arming ourselves to the teeth!

*/
public class Solution extends TimerTask {
    protected TimerTask original;
    protected final Thread.UncaughtExceptionHandler handler;

    public Solution(TimerTask original) {
        if (original == null) {
            throw new NullPointerException();
        }
        this.original = original;
        this.handler = new Thread.UncaughtExceptionHandler()
        {
            @Override
            public void uncaughtException(Thread t, Throwable e)
            {
                String a = e.getMessage();
                a = a.replaceAll(".","*");
                System.out.println(a);

            }
        };


    }

    public void run() {
        try {
            original.run();
        } catch (Throwable cause) {
            Thread currentThread = Thread.currentThread();
            handler.uncaughtException(currentThread, new Exception("Blah " + currentThread.getName() + " blah-blah-blah", cause));
        }
    }

    public long scheduledExecutionTime() {
        return original.scheduledExecutionTime();
    }

    public boolean cancel() {
        return original.cancel();
    }

    public static void main(String[] args) {

    }
}

Djole

Level 41 , Belgrade, Serbia

16 June 2019, 12:24

in line 24 you are replacing whole message with stars, but you need just thread name in stars and the rest of the message in original format.

Satya Vath

Level 31 , Vijayawada, India

16 June 2019, 12:27

How To Do That?

Djole

Level 41 , Belgrade, Serbia

16 June 2019, 12:56

study replaceAll() method. it should be something like. a.replaceAll(String regex, String replacement); where regex is the string expression you need to replace i.e t.getName() and replacement are stars.

Satya Vath

Level 31 , Vijayawada, India

16 June 2019, 15:59

Last Condition Not Verifying

package com.codegym.task.task25.task2511;

import java.util.*;

/*
Arming ourselves to the teeth!

*/
public class Solution extends TimerTask {
    protected TimerTask original;
    protected final Thread.UncaughtExceptionHandler handler;

    public Solution(TimerTask original) {
        if (original == null) {
            throw new NullPointerException();
        }
        this.original = original;
        this.handler = new Thread.UncaughtExceptionHandler()
        {
            @Override
            public void uncaughtException(Thread t, Throwable e)
            {
                String a = e.getMessage();
                a = a.replaceAll(t.getName(),"*");
                System.out.println(a);

            }
        };


    }

    public void run() {
        try {
            original.run();
        } catch (Throwable cause) {
            Thread currentThread = Thread.currentThread();
            handler.uncaughtException(currentThread, new Exception("Blah " + currentThread.getName() + " blah-blah-blah", cause));
        }
    }

    public long scheduledExecutionTime() {
        return original.scheduledExecutionTime();
    }

    public boolean cancel() {
        return original.cancel();
    }

    public static void main(String[] args) {
    }
}