From 4f8260e8bcc81b63c4bf4c9a7d5b1702ca4460a3 Mon Sep 17 00:00:00 2001
From: "Ardyc (Gulyakin Egor)" <42569377+ArhostCode@users.noreply.github.com>
Date: Thu, 4 Jan 2024 11:54:04 +0300
Subject: [PATCH] =?UTF-8?q?=D0=9F=D1=80=D0=BE=D0=B5=D0=BA=D1=82=20?=
 =?UTF-8?q?=E2=84=965=20(#16)?=
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* Done project 5

* Fixes project 5

* Done project 5

* Move project 5 to test to increase coverage
---
 pom.xml                                       |  15 +++
 .../edu/project5/ReflectionBenchmark.java     | 101 ++++++++++++++++++
 2 files changed, 116 insertions(+)
 create mode 100644 src/test/java/edu/project5/ReflectionBenchmark.java

diff --git a/pom.xml b/pom.xml
index c34bdc6..0877fc1 100644
--- a/pom.xml
+++ b/pom.xml
@@ -44,6 +44,7 @@
         <maven-site-plugin.version>4.0.0-M9</maven-site-plugin.version>
 
         <jacoco-maven-plugin.version>0.8.10</jacoco-maven-plugin.version>
+        <jmh.version>1.37</jmh.version>
         <bytebuddy.version>1.14.9</bytebuddy.version>
         <asm.version>9.6</asm.version>
     </properties>
@@ -137,6 +138,20 @@
             <version>5.6.0</version>
             <scope>test</scope>
         </dependency>
+
+        <!-- JMH -->
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-core</artifactId>
+            <version>${jmh.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-generator-annprocess</artifactId>
+            <version>${jmh.version}</version>
+            <scope>provided</scope>
+        </dependency>
+
     </dependencies>
 
     <build>
diff --git a/src/test/java/edu/project5/ReflectionBenchmark.java b/src/test/java/edu/project5/ReflectionBenchmark.java
new file mode 100644
index 0000000..8cb38aa
--- /dev/null
+++ b/src/test/java/edu/project5/ReflectionBenchmark.java
@@ -0,0 +1,101 @@
+package edu.project5;
+
+import java.lang.invoke.LambdaMetafactory;
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Function;
+import lombok.SneakyThrows;
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.Setup;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.infra.Blackhole;
+import org.openjdk.jmh.runner.Runner;
+import org.openjdk.jmh.runner.RunnerException;
+import org.openjdk.jmh.runner.options.Options;
+import org.openjdk.jmh.runner.options.OptionsBuilder;
+import org.openjdk.jmh.runner.options.TimeValue;
+
+@State(Scope.Thread)
+public class ReflectionBenchmark {
+
+    private static final String TESTING_METHOD = "name";
+    private static final int WARMUP_TIME = 5;
+    private static final int MEASUREMENT_TIME = 5;
+
+    @SuppressWarnings("checkstyle:UncommentedMain")
+    public static void main(String[] args) throws RunnerException {
+        Options options = new OptionsBuilder()
+            .include(ReflectionBenchmark.class.getSimpleName())
+            .shouldFailOnError(true)
+            .shouldDoGC(true)
+            .mode(Mode.AverageTime)
+            .timeUnit(TimeUnit.NANOSECONDS)
+            .forks(1)
+            .warmupForks(1)
+            .warmupIterations(1)
+            .warmupTime(TimeValue.seconds(WARMUP_TIME))
+            .measurementIterations(1)
+            .measurementTime(TimeValue.seconds(MEASUREMENT_TIME))
+            .build();
+
+        new Runner(options).run();
+    }
+
+    private Student student;
+    private Method method;
+    private MethodHandle methodHandle;
+    private Function<Student, String> lambdaMetaFactory;
+
+    @SneakyThrows @Setup
+    public void setup() {
+        student = new Student("Egor", "Gulyakin");
+
+        method = Student.class.getMethod(TESTING_METHOD);
+
+        MethodHandles.Lookup publicLookup = MethodHandles.lookup();
+        MethodType methodType = MethodType.methodType(String.class);
+        methodHandle = publicLookup.findVirtual(Student.class, TESTING_METHOD, methodType);
+
+        lambdaMetaFactory = (Function<Student, String>) LambdaMetafactory.metafactory(
+            publicLookup,
+            "apply",
+            MethodType.methodType(Function.class),
+            MethodType.methodType(Object.class, Object.class),
+            methodHandle,
+            MethodType.methodType(String.class, Student.class)
+        ).getTarget().invokeExact();
+    }
+
+    @Benchmark
+    public void directAccess(Blackhole blackhole) {
+        String name = student.name();
+        blackhole.consume(name);
+    }
+
+    @Benchmark
+    public void reflection(Blackhole blackhole) throws InvocationTargetException, IllegalAccessException {
+        String name = (String) method.invoke(student);
+        blackhole.consume(name);
+    }
+
+    @Benchmark
+    public void methodHandle(Blackhole blackhole) throws Throwable {
+        String name = (String) methodHandle.invoke(student);
+        blackhole.consume(name);
+    }
+
+    @Benchmark
+    public void lambdaMetaFactory(Blackhole blackhole) {
+        String name = lambdaMetaFactory.apply(student);
+        blackhole.consume(name);
+    }
+
+    private record Student(String name, String surname) {
+    }
+}