iSharkFly-Docs
/
java-tutorials
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Josh Cummings suggestions: Package renamed and Benchmark using JMH

This commit is contained in:
Fabio Silva 2019-12-12 09:52:43 -03:00
parent 9f78f62732
commit 2d6be72eab
4 changed files with 79 additions and 46 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
core-java-modules/core-java-11/src/test/java/com/baeldung/pattern/PatternJava11UnitTest.java → core-java-modules/core-java-11/src/test/java/com/baeldung/patternreuse/PatternJava11UnitTest.java
View File

@ -1,4 +1,4 @@
package com.baeldung.pattern;
package com.baeldung.patternreuse;
import org.junit.jupiter.api.Test;

13
core-java-modules/core-java-text/pom.xml
View File

@ -13,6 +13,19 @@
<relativePath>../../parent-java</relativePath>
</parent>
<dependencies>
<dependency>
<groupId>org.openjdk.jmh</groupId>
<artifactId>jmh-core</artifactId>
<version>${jmh-core.version}</version>
</dependency>
<dependency>
<groupId>org.openjdk.jmh</groupId>
<artifactId>jmh-generator-annprocess</artifactId>
<version>${jmh-core.version}</version>
</dependency>
</dependencies>
<build>
<finalName>core-java-text</finalName>
<resources>

108
core-java-modules/core-java-text/src/main/java/com/baeldung/pattern/PatternPerformanceComparison.java → core-java-modules/core-java-text/src/main/java/com/baeldung/patternreuse/PatternPerformanceComparison.java
View File

@ -1,68 +1,88 @@
package com.baeldung.pattern;
package com.baeldung.patternreuse;
import java.time.Duration;
import org.openjdk.jmh.annotations.*;
import org.openjdk.jmh.runner.RunnerException;
import java.io.IOException;
import java.time.Instant;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MILLISECONDS)
@Fork(value = 1, warmups = 1)
@Warmup(iterations = 5)
@State(Scope.Benchmark)
public class PatternPerformanceComparison {
private static final String PATTERN = "\\d*[02468]";
private static List<String> values;
public static void main(String[] args) {
loadValues();
private static Matcher matcherFromPreCompiledPattern;
private static Pattern preCompiledPattern;
public static void main(String[] args) throws IOException, RunnerException {
org.openjdk.jmh.Main.main(args);
}
@Benchmark
public void matcherFromPreCompiledPatternResetMatches() {
//With pre-compiled pattern and reusing the matcher
// 1 Pattern object created
// 1 Matcher objects created
for (String value : values) {
matcherFromPreCompiledPattern.reset(value).matches();
}
}
@Benchmark
public void preCompiledPatternMatcherMatches() {
// With pre-compiled pattern
// 1 Pattern object created
// 5_000_000 Matcher objects created
for (String value : values) {
preCompiledPattern.matcher(value).matches();
}
}
@Benchmark
public void patternCompileMatcherMatches() {
// Above approach "Pattern.matches(PATTERN, value)" makes this internally
// 5_000_000 Pattern objects created
// 5_000_000 Matcher objects created
for (String value : values) {
Pattern.compile(PATTERN).matcher(value).matches();
}
}
@Benchmark
public void patternMatches() {
// Above approach "value.matches(PATTERN)" makes this internally
// 5_000_000 Pattern objects created
// 5_000_000 Matcher objects created
for (String value : values) {
Pattern.matches(PATTERN, value);
}
}
@Benchmark
public void stringMatchs() {
// 5_000_000 Pattern objects created
// 5_000_000 Matcher objects created
Instant start = Instant.now();
for (String value : values) {
value.matches(PATTERN);
}
System.out.println(Duration.between(start, Instant.now()).toMillis() + "ms -> String.matchs(regex)");
// Above approach "value.matches(PATTERN)" makes this internally
// 5_000_000 Pattern objects created
// 5_000_000 Matcher objects created
start = Instant.now();
for (String value : values) {
Pattern.matches(PATTERN, value);
}
System.out.println(Duration.between(start, Instant.now()).toMillis() + "ms -> Pattern.matches(regex, charSequence)");
// Above approach "Pattern.matches(PATTERN, value)" makes this internally
// 5_000_000 Pattern objects created
// 5_000_000 Matcher objects created
start = Instant.now();
for (String value : values) {
Pattern.compile(PATTERN).matcher(value).matches();
}
System.out.println(Duration.between(start, Instant.now()).toMillis() + "ms -> Pattern.compile(regex).matcher(charSequence).matches()");
// With pre-compiled pattern
// 1 Pattern object created
// 5_000_000 Matcher objects created
Pattern preCompiledPattern = Pattern.compile(PATTERN);
start = Instant.now();
for (String value : values) {
preCompiledPattern.matcher(value).matches();
}
System.out.println(Duration.between(start, Instant.now()).toMillis() + "ms -> preCompiledPattern.matcher(value).matches()");
//With pre-compiled pattern and reusing the matcher
// 1 Pattern object created
// 1 Matcher objects created
Matcher matcherFromPreCompiledPattern = preCompiledPattern.matcher("");
start = Instant.now();
for (String value : values) {
matcherFromPreCompiledPattern.reset(value).matches();
}
System.out.println(Duration.between(start, Instant.now()).toMillis() + "ms -> matcherFromPreCompiledPattern.reset(value).matches()");
}
private static void loadValues() {
@Setup()
public void setUp() {
preCompiledPattern = Pattern.compile(PATTERN);
matcherFromPreCompiledPattern = preCompiledPattern.matcher("");
values = new ArrayList<>();
for (int x = 1; x <= 5_000_000; x++) {
values.add(String.valueOf(x));

2
core-java-modules/core-java-text/src/test/java/com/baeldung/pattern/PatternUnitTest.java → core-java-modules/core-java-text/src/test/java/com/baeldung/patternreuse/PatternUnitTest.java
View File

@ -1,4 +1,4 @@
package com.baeldung.pattern;
package com.baeldung.patternreuse;
import org.junit.jupiter.api.Test;