Java使用JaCoCo进行代码覆盖率分析的操作指南

<build>
    <plugins>
        <plugin>
            <groupId>org.jacoco</groupId>
            <artifactId>jacoco-maven-plugin</artifactId>
            <version>0.8.10</version>
            <executions>
                <execution>
                    <goals>
                        <goal>prepare-agent</goal>
                    </goals>
                </execution>
                <execution>
                    <id>report</id>
                    <phase>verify</phase>
                    <goals>
                        <goal>report</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

<configuration>
    <rules>
        <rule>
            <element>PACKAGE</element>
            <limits>
                <limit>
                    <counter>LINE</counter>
                    <value>COVEREDRATIO</value>
                    <minimum>0.8</minimum>
                </limit>
            </limits>
        </rule>
    </rules>
</configuration>

src/
├── main/
│   └── java/
│       └── com/example/
│           └── Calculator.java
├── test/
    └── java/
        └── com/example/
            └── CalculatorTest.java

package com.example;

public class Calculator {
    public int add(int a, int b) {
        return a + b;
    }

    public int subtract(int a, int b) {
        return a - b;
    }

    public int multiply(int a, int b) {
        return a * b;
    }

    public int divide(int a, int b) {
        if (b == 0) {
            throw new IllegalArgumentException("Division by zero");
        }
        return a / b;
    }
}

package com.example;

import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.*;

class CalculatorTest {

    @Test
    void testAdd() {
        Calculator calculator = new Calculator();
        assertEquals(5, calculator.add(2, 3));
    }

    @Test
    void testSubtract() {
        Calculator calculator = new Calculator();
        assertEquals(1, calculator.subtract(3, 2));
    }

    @Test
    void testMultiply() {
        Calculator calculator = new Calculator();
        assertEquals(6, calculator.multiply(2, 3));
    }

    @Test
    void testDivide() {
        Calculator calculator = new Calculator();
        assertEquals(2, calculator.divide(6, 3));
    }

    @Test
    void testDivideByZero() {
        Calculator calculator = new Calculator();
        assertThrows(IllegalArgumentException.class, () -> calculator.divide(6, 0));
    }
}

mvn clean verify