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 * Licensed under the Apache License, Version 2.0 (the "License");
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package org.springframework.core;

Default implementation of the ParameterNameDiscoverer strategy interface, using the Java 8 standard reflection mechanism (if available), and falling back to the ASM-based LocalVariableTableParameterNameDiscoverer for checking debug information in the class file.

If a Kotlin reflection implementation is present, KotlinReflectionParameterNameDiscoverer is added first in the list and used for Kotlin classes and interfaces. When compiling or running as a GraalVM native image, the KotlinReflectionParameterNameDiscoverer is not used.

Further discoverers may be added through PrioritizedParameterNameDiscoverer.addDiscoverer(ParameterNameDiscoverer).

Author:Juergen Hoeller, Sebastien Deleuze, Sam Brannen
See Also:
Since:4.0
/** * Default implementation of the {@link ParameterNameDiscoverer} strategy interface, * using the Java 8 standard reflection mechanism (if available), and falling back * to the ASM-based {@link LocalVariableTableParameterNameDiscoverer} for checking * debug information in the class file. * * <p>If a Kotlin reflection implementation is present, * {@link KotlinReflectionParameterNameDiscoverer} is added first in the list and * used for Kotlin classes and interfaces. When compiling or running as a GraalVM * native image, the {@code KotlinReflectionParameterNameDiscoverer} is not used. * * <p>Further discoverers may be added through {@link #addDiscoverer(ParameterNameDiscoverer)}. * * @author Juergen Hoeller * @author Sebastien Deleuze * @author Sam Brannen * @since 4.0 * @see StandardReflectionParameterNameDiscoverer * @see LocalVariableTableParameterNameDiscoverer * @see KotlinReflectionParameterNameDiscoverer */
public class DefaultParameterNameDiscoverer extends PrioritizedParameterNameDiscoverer {
Whether this environment lives within a native image. Exposed as a private static field rather than in a NativeImageDetector.inNativeImage() static method due to https://github.com/oracle/graal/issues/2594.
See Also:
/** * Whether this environment lives within a native image. * Exposed as a private static field rather than in a {@code NativeImageDetector.inNativeImage()} static method due to https://github.com/oracle/graal/issues/2594. * @see <a href="https://github.com/oracle/graal/blob/master/sdk/src/org.graalvm.nativeimage/src/org/graalvm/nativeimage/ImageInfo.java">ImageInfo.java</a> */
private static final boolean IN_NATIVE_IMAGE = (System.getProperty("org.graalvm.nativeimage.imagecode") != null); public DefaultParameterNameDiscoverer() { if (KotlinDetector.isKotlinReflectPresent() && !IN_NATIVE_IMAGE) { addDiscoverer(new KotlinReflectionParameterNameDiscoverer()); } addDiscoverer(new StandardReflectionParameterNameDiscoverer()); addDiscoverer(new LocalVariableTableParameterNameDiscoverer()); } }