# Advanced Programing - 8 Report

## Theoretical Questions Answers

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## 1. start() vs run()
### Output:

Calling run()

Running in: main

Calling start()

Running in: Thread-2

### Explanation 
When calling "t1.run()" directly, the run method executes in the current thread (main).
When calling "t2.start()" , java creates a new thread and executes run() in that thread (Thread-2).

### Difference:

|start()|run()|
|-------|-----|
|Creates new thread|No new thread|
|Executes run() in new thread|Executed like nurmal method|
|Can only be called once|Can be called multiple times|

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## Deamon Threads

### Output(with demon):

Main thread ends

Deamon thread running...

(Program terminates quickly)

### Output(without demon):

Main thread ends.

Deamon thread running...

(20 times)

### Explanation
A daemon thread is a background thread that does NOT prevent the JVM from exiting.
When the main thread (non-daemon) finishes, 
the JVM checks if there are any non-daemon threads still running.
Since only the daemon thread remains,
the JVM terminates immediately without waiting for the daemon thread to complete its 20 iterations.

Without setDaemon(true), the thread becomes a user thread (non-daemon) .
User threads prevent the JVM from exiting until they complete.
Therefore, the JVM waits for the thread to finish all 20 iterations before terminating the program.

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### Real-life use cases:
1. Garbage Collector (GC)
2. Auto-save features
3. Background logging
4. Session cleanup in web servers

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## 3. Lambda Expressions

### Output:

Thread is running using a...!

### What is `() -> {}`?
This is a **Lambda Expression** introduced in Java.


### Comparison:

| Traditional | Lambda |
|-------------|--------|
| Needs separate class | No separate class |
| More code | Concise |
| `new Thread(new Runnable(){...})` | `new Thread(() -> {...})` |

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