Package org.gnome.glib

Class Mutex

java.lang.Object

io.github.jwharm.javagi.base.ProxyInstance

org.gnome.glib.Mutex

All Implemented Interfaces:

Proxy

@Generated("io.github.jwharm.JavaGI")
public class Mutex
extends ProxyInstance

The GMutex struct is an opaque data structure to represent a mutex (mutual exclusion). It can be used to protect data against shared access.

Take for example the following function:

  int
   give_me_next_number (void)
   {
     static int current_number = 0;

     // now do a very complicated calculation to calculate the new
     // number, this might for example be a random number generator
     current_number = calc_next_number (current_number);

     return current_number;
   }
 

It is easy to see that this won't work in a multi-threaded application. There current_number must be protected against shared access. A GMutex can be used as a solution to this problem:

  int
   give_me_next_number (void)
   {
     static GMutex mutex;
     static int current_number = 0;
     int ret_val;

     g_mutex_lock (&mutex);
     ret_val = current_number = calc_next_number (current_number);
     g_mutex_unlock (&mutex);

     return ret_val;
   }
 

Notice that the GMutex is not initialised to any particular value. Its placement in static storage ensures that it will be initialised to all-zeros, which is appropriate.

If a GMutex is placed in other contexts (eg: embedded in a struct) then it must be explicitly initialised using g_mutex_init().

A GMutex should only be accessed via g_mutex_ functions.

Constructor Summary

Constructors

Constructor	Description
Mutex(Arena arena)	Allocate a new Mutex.
Mutex(MemorySegment address)	Create a Mutex proxy instance for the provided memory address.

Method Summary

Modifier and Type	Method	Description
static MemoryLayout	getMemoryLayout()	The memory layout of the native struct.
static Mutex	new_()	Deprecated. GMutex can now be statically allocated, or embedded in structures and initialised with g_mutex_init().

Methods inherited from class io.github.jwharm.javagi.base.ProxyInstance

equals, handle, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Mutex

public Mutex(MemorySegment address)

Create a Mutex proxy instance for the provided memory address.

Parameters:

address - the memory address of the native object

Mutex

public Mutex(Arena arena)

Allocate a new Mutex.

Parameters:

arena - to control the memory allocation scope

Method Details

getMemoryLayout

public static MemoryLayout getMemoryLayout()

The memory layout of the native struct.

Returns:

the memory layout

new_

@Deprecated
public static Mutex new_()

Deprecated.

GMutex can now be statically allocated, or embedded in structures and initialised with g_mutex_init().

Allocates and initializes a new GMutex.

Returns:

a newly allocated GMutex. Use g_mutex_free() to free