org.graalvm.nativeimage.c.struct.CFieldOffset Maven / Gradle / Ivy
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* particular file as subject to the "Classpath" exception as provided
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* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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package org.graalvm.nativeimage.c.struct;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import org.graalvm.word.WordBase;
/**
* Denotes a method as a field offset access of a {@link CStruct C struct}. The method must not have
* any parameters. The return type must be a primitive integer type or a {@link WordBase word type}.
*
* Calls to the method are replaced with a compile time constant. If the annotation is used on a
* non-static method, the receiver is ignored. Java does not allow an interface method to be
* declared {@code static native}. So the annotated method must either be non-static (with the
* receiver being ignored), or static but non-native (with the method body being ignored).
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.METHOD})
public @interface CFieldOffset {
/**
* Specifies the field name inside the {@link CStruct C struct}. If no name is provided, the
* method name is used as the field name. A possible "offsetOf" prefix of the method name is
* removed.
*/
String value() default "";
}