39 lines
1.1 KiB
Java
39 lines
1.1 KiB
Java
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package ex2;
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import java.util.HashMap;
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import java.util.Map;
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import java.util.concurrent.atomic.LongAdder;
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public final class Profiler {
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// not concurrent on purpose, since the value of the map is computed with a pure function
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// on the map key, and thus we don't care if the value is overwritten as a result of a
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// race condition
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private static final Map<Class<?>, Boolean> isThread = new HashMap<>();
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private static final LongAdder reads = new LongAdder();
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private static final LongAdder writes = new LongAdder();
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static {
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Runtime.getRuntime().addShutdownHook(new Thread(() -> {
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System.out.printf("Instance field read access: %d\nInstance field write access: %d\n",
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reads.longValue(),
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writes.longValue());
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}));
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}
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private Profiler() {
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}
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public static boolean isThread(final Class<?> clazz) {
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return isThread.computeIfAbsent(clazz, Thread.class::isAssignableFrom);
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}
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public static void increment(long readCount, long writeCount) {
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reads.add(readCount);
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writes.add(writeCount);
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}
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}
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