Easy Notes Of Java programming unit-3 @Computer Diploma

Description

3.1 Errors and Exception

Errors:

• Compile-time errors: Syntax errors.
• Runtime errors: Logic errors, exceptions.
• Logical errors: Incorrect program logic.

Exceptions:

• Exception handling: Managing runtime errors.
• try block: Code that might throw an exception.
• catch block: Handles a specific exception.
• finally block: Code that always executes.
• throws keyword: Declares an exception.
• throw keyword: Throws an exception.
• Built-in exceptions: IOException, SQLException, ArithmeticException.
• Custom exceptions: User-defined exceptions.

3.2 Multithreaded programming

Creating a Thread:

• Thread class: Extending the Thread class.
• Runnable interface: Implementing the Runnable interface.
• run() method: Contains thread’s code.
• start() method: Starts thread execution.

Thread Life Cycle:

• New: Just created.
• Runnable: Ready to run.
• Running: Currently executing.
• Blocked/Waiting: Paused, waiting for an event.
• Terminated/Dead: Finished execution.

Thread Methods:

• sleep(): Pauses thread.
• join(): Waits for a thread to finish.
• yield(): Gives up CPU time.
• interrupt(): Interrupts a thread.

Synchronization:

• synchronized keyword: Prevents simultaneous access.
• Race condition: Multiple threads accessing shared data.
• Deadlock: Two or more threads blocked indefinitely.