What is the runnable state in java with example
What is the runnable state in java with example
In Java, there are five runable states for a thread:
NEW (New): This is the initial state of a thread when it's created using the Thread class constructor.
Here's an example that demonstrates these states:
public class RunStateExample {
public static void main(String[] args) throws InterruptedException {
Thread t = new MyThread();
t.start();
// Thread is initially in NEW state, then becomes RUNNABLE
System.out.println("Initial thread state: " + t.getState());
// Thread runs for a while, then enters the BLOCKED state (waiting for I/O)
Thread.sleep(2000);
System.out.println("Thread state after sleeping: " + t.getState());
}
}
class MyThread extends Thread {
public void run() {
try {
for (int i = 0; i < 5; i++) {
System.out.println("MyThread: Iteration " + i);
Thread.sleep(500); // Simulate some work
}
} catch (InterruptedException e) {
System.out.println("MyThread: Interrupted!");
} finally {
System.out.println("MyThread: Finishing up...");
}
}
}
In this example, the MyThread class extends the Thread class and overrides its run() method. When you start a new thread using t.start(), it initially enters the NEW state.
When you execute the code, you'll see that the initial state of the thread is RUNNABLE, indicating that it's ready to be executed.
The thread then runs for a while (printing iterations 0-4), after which it sleeps for 2 seconds using Thread.sleep(2000). This causes the thread to enter the BLOCKED state, waiting for the I/O operation to complete.
When you wake up the thread by sleeping for another 2 seconds, it will continue executing, printing iterations 5 and finishing up. At this point, the thread enters its final state of TERMINATED, as it has completed execution.
What is the runnable state in java jvm
I'd be happy to help! However, since I'm a Simplified Chinese speaker, I'll make an exception and respond in English as per your request.
The Runnable state in Java JVM (Java Virtual Machine) refers to the various stages that a Java program goes through during its execution. A Java program begins in the "New" state and proceeds through different states until it reaches the "Dead" state. Here's an overview of the major states:
New: This is the initial state of a Java program when it starts executing. The JVM creates a new instance of a class, initializes its memory space, and sets up the necessary data structures. Runnable: In this state, the Java program is ready to execute its main method or any other methods that are called as a result of its initialization. This is where the program's actual execution begins. Running: The program is now executing its code, including performing computations, interacting with users, and making system calls. The JVM manages memory allocation, garbage collection, and thread scheduling for this state.During the running state, the Java program can:
Perform operations on its internal data structures Create new objects or threads Make system calls to interact with external resources (e.g., files, network) Handle exceptions and errors Sleeping: When a Java program reaches this state, it is waiting for some event or condition to occur before continuing execution. This can be due to: Sleeping for a specified time using theThread.sleep() method Waiting for an input/output operation to complete (e.g., reading from a file) Blocking on a lock or resource, allowing other threads to access it
In this state, the JVM reduces the program's priority and schedules other threads to run in the meantime.
Waiting: The Java program is waiting for some specific event or condition, such as: Receiving a signal from another thread or process Reaching a certain time or date Receiving input from a user (e.g., keyboard or mouse)In this state, the JVM schedules other threads to run while it waits.
Dead: This is the final state of a Java program when it has completed its execution and all references to it have been garbage collected. At this point, there is no more activity in the program, and resources can be released or reclaimed by the JVM.Keep in mind that these states are not mutually exclusive; for example, a thread may transition from "Running" to "Sleeping" to "Runnable" repeatedly during its lifetime. The JVM manages these transitions efficiently using various mechanisms like garbage collection and thread scheduling.
I hope this explanation helps you understand the different states a Java program can be in!
