The ______ Pattern is a design pattern that prevents a specific action from occurring multiple times when it should only happen once, based on a predefined condition. It avoids redundancy and ensures actions are taken when needed.
- Thread Pool
- Balking
- Read-Write Lock
- Producer-Consumer
Answer:
The Balking Pattern is a design pattern in software development used to prevent an action or process from taking place multiple times when it should only occur once under certain conditions. It's employed to avoid unnecessary or redundant operations and ensure that a specific task is carried out when appropriate conditions are met.
Example of balking pattern applied to a printer:
public class Printer { private boolean isPrinting = false;
public synchronized void printDocument(String document) {
if (isPrinting) {
System.out.println("Printer is busy. Please wait.");
return; // Balking if a print job is already in progress
}
isPrinting = true; // Mark the printer as busy
System.out.println("Printing document: " + document);
// Simulate printing time
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
isPrinting = false; // Mark the printer as free
}
}
}
Key components and concepts of the Balking Pattern:
- Guard Condition: A Guard Condition is a condition or check that determines whether a particular action or process should proceed. If the condition is not met, the action is "balked" or skipped.
- Balking: Balking is the act of avoiding or skipping an action or process when the Guard Condition indicates that it's unnecessary or inappropriate to proceed.
The Balking Pattern helps to ensure that actions are taken only when required, reducing unnecessary resource consumption and preventing unintended side effects. It's often used in scenarios where actions need to be synchronized or coordinated, and it helps prevent race conditions or conflicts.