Java regex word boundary with special characters at the beginning or end of regex (dot, plus, underscore, dash)

import org.junit.Test;

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import java.util.regex.Matcher;

import java.util.regex.Pattern;

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import static org.assertj.core.api.Assertions.assertThat;

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public class RegexWordBoundaryTests {

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    @Test

    public void regexWordBoundaryTest1() {

        Pattern pattern = Pattern.compile("\\.NET", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher(".NET");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo(".NET");

    }

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    @Test

    public void regexWordBoundaryTest2() {

        Pattern pattern = Pattern.compile("\\.\\bNET\\b", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher(".NET");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo(".NET");

    }

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    @Test

    public void regexWordBoundaryTest3() {

        // if word starts with '.' and ends with '.'

        Pattern pattern = Pattern.compile("\\.\\bNET\\b\\.", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test .NET. test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo(".NET.");

    }

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    @Test

    public void regexWordBoundaryTest4() {

        Pattern pattern = Pattern.compile("\\bC\\b#", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test C# test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("C#");

    }

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    @Test

    public void regexWordBoundaryTest5() {

        Pattern pattern = Pattern.compile("\\bC-sharp\\b", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test C-sharp test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("C-sharp");

    }

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    @Test

    public void regexWordBoundaryTest6() {

        Pattern pattern = Pattern.compile("\\bC_sharp\\b", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test C_sharp test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("C_sharp");

    }

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    @Test

    public void regexWordBoundaryTest7() {

        Pattern pattern = Pattern.compile("\\bnode\\.js\\b", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test node.js test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("node.js");

    }

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    @Test

    public void regexWordBoundaryTest8() {

        // if word starts with '-'

        Pattern pattern = Pattern.compile("-\\bnode\\b", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test -node test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("-node");

    }

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    @Test

    public void regexWordBoundaryTest9() {

        // if word starts with '-'

        Pattern pattern = Pattern.compile("\\bC\\b\\+\\+", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test C++ test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("C++");

    }

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    @Test

    public void regexWordBoundaryTest10() {

        Pattern pattern = Pattern.compile("\\bC/C\\b\\+\\+", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test C/C++ test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("C/C++");

    }

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    @Test

    public void regexWordBoundaryTest11() {

        Pattern pattern = Pattern.compile("\\bC/Cpp\\b", Pattern.CASE_INSENSITIVE);

        Matcher matcher = pattern.matcher("test C/Cpp test");

        assertThat(matcher.find()).isTrue();

        assertThat(matcher.group()).isEqualTo("C/Cpp");

    }

}