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/*
* Copyright 2018 dorkbox, llc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package dorkbox.util.jna.macos.foundation;
import com.sun.jna.Callback;
import com.sun.jna.Library;
import com.sun.jna.Native;
import com.sun.jna.Pointer;
/**
* "how to" from: https://gist.github.com/3974488
*
* https://developer.apple.com/documentation/objectivec/objective-c_runtime
*
* We cannot use JNA "direct mapping", because direct mapping DOES NOT support var-args (which `objc_msgSend` requires)
*/
public
class ObjectiveC {
interface Objc extends Library {
Pointer objc_lookUpClass(String name);
long objc_msgSend(Pointer theReceiver, Pointer theSelector, Object... string);
Pointer objc_allocateClassPair(Pointer superClass, String name, long extraBytes);
void objc_registerClassPair(Pointer clazz);
Pointer class_createInstance(Pointer clazz, int extraBytes);
boolean class_addMethod(Pointer clazz, Pointer selector, Callback callback, String types);
Pointer sel_getUid(String name);
Pointer sel_registerName(String name);
}
private static final Objc INSTANCE = Native.loadLibrary("objc", Objc.class);
/**
* Returns the class definition of a specified class.
*
* @param name The name of the class to look up.
*
* @return The Class object for the named class, or nil if the class is not registered with the Objective-C runtime.
*/
public static
Pointer objc_lookUpClass(String name) {
return INSTANCE.objc_lookUpClass(name);
}
/**
* Sends a message with a simple return value to an instance of a class.
*
* @param self A pointer that points to the instance of the class that is to receive the message.
* @param op The selector of the method that handles the message.
* @param args A variable argument list containing the arguments to the method.
*
* @return The return value of the method.
*/
public static
long objc_msgSend(Pointer self, Pointer op, Object... args) {
return INSTANCE.objc_msgSend(self, op, args);
}
/**
* Creates a new class and metaclass.
*
* @param superClass The class to use as the new class's superclass, or Nil to create a new root class.
* @param name The string to use as the new class's name. The string will be copied.
* @param extraBytes The number of bytes to allocate for indexed ivars at the end of the class and metaclass objects. This should usually be 0.
*
* @return The new class, or Nil if the class could not be created (for example, the desired name is already in use).
*/
public static
Pointer objc_allocateClassPair(Pointer superClass, String name, long extraBytes) {
return INSTANCE.objc_allocateClassPair(superClass, name, extraBytes);
}
/**
* Registers a class that was allocated using objc_allocateClassPair.
*
* @param cls The class you want to register.
*/
public static
void objc_registerClassPair(Pointer cls) {
INSTANCE.objc_registerClassPair(cls);
}
/**
* Creates an instance of a class, allocating memory for the class in the default malloc memory zone.
*
* @param cls The class that you want to allocate an instance of.
* @param extraBytes An integer indicating the number of extra bytes to allocate. The additional bytes can be used to store additional instance variables beyond those defined in the class definition.
*
* @return An instance of the class cls.
*/
public static
Pointer class_createInstance(Pointer cls, int extraBytes) {
return INSTANCE.class_createInstance(cls, extraBytes);
}
/**
* Adds a new method to a class with a given name and implementation.
* NOTE: class_addMethod will add an override of a superclass's implementation, but will not replace an existing implementation in this class. To change an existing implementation, use method_setImplementation.
*
* @param cls The class to which to add a method.
* @param name A selector that specifies the name of the method being added.
* @param imp A function which is the implementation of the new method. The function must take at least two arguments—self and _cmd.
* @param types An array of characters that describe the types of the arguments to the method. For possible values, see Objective-C Runtime Programming Guide > Type Encodings. Since the function must take at least two arguments—self and _cmd, the second and third characters must be “@:” (the first character is the return type).
*
* @return YES if the method was added successfully, otherwise NO (for example, the class already contains a method implementation with that name).
*/
public static
boolean class_addMethod(Pointer cls, Pointer name, Callback imp, String types) {
return INSTANCE.class_addMethod(cls, name, imp, types);
}
/**
* Registers a method name with the Objective-C runtime system.
* NOTE: The implementation of this method is identical to the implementation of sel_registerName.
*
* @param str A pointer to a C string. Pass the name of the method you wish to register.
*
* @return A pointer of type SEL specifying the selector for the named method.
*/
public static
Pointer sel_getUid(String str) {
return INSTANCE.sel_getUid(str);
}
/**
* Registers a method with the Objective-C runtime system, maps the method name to a selector, and returns the selector value.
* NOTE: You must register a method name with the Objective-C runtime system to obtain the method’s selector before you can add the method to a class definition. If the method name has already been registered, this function simply returns the selector.
*
* @param str A pointer to a C string. Pass the name of the method you wish to register.
*
* @return A pointer of type SEL specifying the selector for the named method.
*/
public static
Pointer sel_registerName(String str) {
return INSTANCE.sel_registerName(str);
}
}