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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * accompanied this code).
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package com.oracle.truffle.tools.profiler.impl;

import org.graalvm.options.OptionDescriptors;
import org.graalvm.polyglot.Engine;
import org.graalvm.polyglot.Instrument;

import com.oracle.truffle.api.instrumentation.SourceSectionFilter;
import com.oracle.truffle.api.instrumentation.TruffleInstrument;
import com.oracle.truffle.tools.profiler.CPUSampler;

import static com.oracle.truffle.tools.profiler.impl.CPUSamplerCLI.GATHER_HIT_TIMES;

The instrument for the CPU sampler. 
Since:
0.30/**
 * The {@linkplain TruffleInstrument instrument} for the CPU sampler.
 *
 * @since 0.30
 */
@TruffleInstrument.Registration(id = CPUSamplerInstrument.ID, name = "CPU Sampler", version = CPUSamplerInstrument.VERSION, services = {CPUSampler.class})
public class CPUSamplerInstrument extends TruffleInstrument {

    
Default constructor.
Since:
0.30/**
     * Default constructor.
     *
     * @since 0.30
     */
    public CPUSamplerInstrument() {
    }

    
A string used to identify the sampler, i.e. as the name of the tool.
Since:
0.30/**
     * A string used to identify the sampler, i.e. as the name of the tool.
     *
     * @since 0.30
     */
    public static final String ID = "cpusampler";
    static final String VERSION = "0.4.0";
    private CPUSampler sampler;
    private static ProfilerToolFactory<CPUSampler> factory;

    
Sets the factory which instantiates the CPUSampler. 
Params:
factory – the factory which instantiates the CPUSampler.
Since:
0.30/**
     * Sets the factory which instantiates the {@link CPUSampler}.
     *
     * @param factory the factory which instantiates the {@link CPUSampler}.
     * @since 0.30
     */
    public static void setFactory(ProfilerToolFactory<CPUSampler> factory) {
        if (factory == null || !factory.getClass().getName().startsWith("com.oracle.truffle.tools.profiler")) {
            throw new IllegalArgumentException("Wrong factory: " + factory);
        }
        CPUSamplerInstrument.factory = factory;
    }

    static {
        // Be sure that the factory is initialized:
        try {
            Class.forName(CPUSampler.class.getName(), true, CPUSampler.class.getClassLoader());
        } catch (ClassNotFoundException ex) {
            // Can not happen
            throw new AssertionError();
        }
    }

    
Does a lookup in the runtime instruments of the engine and returns an instance of the CPUSampler. 
Since:
0.33/**
     * Does a lookup in the runtime instruments of the engine and returns an instance of the
     * {@link CPUSampler}.
     *
     * @since 0.33
     */
    public static CPUSampler getSampler(Engine engine) {
        Instrument instrument = engine.getInstruments().get(ID);
        if (instrument == null) {
            throw new IllegalStateException("Sampler is not installed.");
        }
        return instrument.lookup(CPUSampler.class);
    }

    
Called to create the Instrument.
Params:
env – environment information for the instrument
Since:
0.30/**
     * Called to create the Instrument.
     *
     * @param env environment information for the instrument
     * @since 0.30
     */
    @Override
    protected void onCreate(Env env) {
        sampler = factory.create(env);
        if (env.getOptions().get(CPUSamplerCLI.ENABLED)) {
            sampler.setPeriod(env.getOptions().get(CPUSamplerCLI.SAMPLE_PERIOD));
            sampler.setDelay(env.getOptions().get(CPUSamplerCLI.DELAY_PERIOD));
            sampler.setStackLimit(env.getOptions().get(CPUSamplerCLI.STACK_LIMIT));
            sampler.setFilter(getSourceSectionFilter(env));
            sampler.setGatherSelfHitTimes(env.getOptions().get(GATHER_HIT_TIMES));
            sampler.setMode(env.getOptions().get(CPUSamplerCLI.MODE));
            sampler.setCollecting(true);
        }
        env.registerService(sampler);
    }

    private static SourceSectionFilter getSourceSectionFilter(Env env) {
        final CPUSampler.Mode mode = env.getOptions().get(CPUSamplerCLI.MODE);
        final boolean statements = mode == CPUSampler.Mode.STATEMENTS;
        final boolean internals = env.getOptions().get(CPUSamplerCLI.SAMPLE_INTERNAL);
        final Object[] filterRootName = env.getOptions().get(CPUSamplerCLI.FILTER_ROOT);
        final Object[] filterFile = env.getOptions().get(CPUSamplerCLI.FILTER_FILE);
        final String filterMimeType = env.getOptions().get(CPUSamplerCLI.FILTER_MIME_TYPE);
        final String filterLanguage = env.getOptions().get(CPUSamplerCLI.FILTER_LANGUAGE);
        return CPUSamplerCLI.buildFilter(true, statements, false, internals, filterRootName, filterFile, filterMimeType, filterLanguage);
    }

    
Returns:
All the options provided by the CPUSampler.
Since:
0.30/**
     * @return All the {@link OptionDescriptors options} provided by the {@link CPUSampler}.
     * @since 0.30
     */
    @Override
    protected OptionDescriptors getOptionDescriptors() {
        return new CPUSamplerCLIOptionDescriptors();
    }

    
Called when the Instrument is to be disposed.
Params:
env – environment information for the instrument
Since:
0.30/**
     * Called when the Instrument is to be disposed.
     *
     * @param env environment information for the instrument
     * @since 0.30
     */
    @Override
    protected void onDispose(Env env) {
        if (env.getOptions().get(CPUSamplerCLI.ENABLED)) {
            CPUSamplerCLI.handleOutput(env, sampler);
        }
        sampler.close();
    }
}