LoadSourceListener.java

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package com.oracle.truffle.api.instrumentation;

import com.oracle.truffle.api.TruffleRuntime;
import com.oracle.truffle.api.nodes.Node;
import com.oracle.truffle.api.nodes.RootNode;
import com.oracle.truffle.api.source.Source;

/**
 * A listener attached by an {@link Instrumenter} to specific locations of a guest language program
 * to listen to load source events.
 *
 * @since 0.15
 */
public interface LoadSourceListener {

    /**
     * Invoked whenever a new {@link Source source} is loaded.The order in which multiple source
     * event listeners are notified matches the order they are
     * {@link Instrumenter#attachLoadSourceListener(com.oracle.truffle.api.instrumentation.SourceSectionFilter, com.oracle.truffle.api.instrumentation.LoadSourceListener, boolean)
     * attached}.
     * <p>
     * <b>Implementation Note:</b> Source load events are notified when the guest language
     * implementation uses a new {@link Source source} by invoking
     * {@link TruffleRuntime#createCallTarget(RootNode)} with a root node that uses a new source in
     * {@link Node#getSourceSection()}. It assumes that all nodes of an AST have the same
     * {@link Source source} as their root.
     * </p>
     *
     * @param event an event with context information
     * @since 0.15
     */
    void onLoad(LoadSourceEvent event);

}