junit unit test, parameterized settings

topic

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class under test

public class java4 {
public String data(String x) {
	//判断x是否以字母开头，位数在2位以上
	//" ^ "是已什么开头，写法:”^[a-z]“意思是以a-z开头
	//”{2，}“意思是两位以上字符
	//”{0，9}“意思是9位字符以内
	if (x.matches("(^[a-z][a-zA-Z]{2,})$")){
		//x是否以ab开头
		if (x.startsWith("ab")){
			//将ab开头改为ef开头
			System.out.println(x.replaceFirst("ab", "ef"));
			return x.replaceFirst("ab", "ef");
		}
		//x不以ab开头，以cd结尾
		else if (!x.startsWith("ab")&&x.endsWith("cd")) {
			//将所有cd变换为gh
			System.out.println(x.replace("cd", "gh"));
			return x.replace("cd", "gh");
		}else {
			//将所有字母转换为大写
			System.out.println(x.toUpperCase());
			return x.toUpperCase();
		}
	}
	else {
		return null;
	}
}
}

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Test class parameterization settings

Declare variables, test data, and expected outcome variable declarations, including special runners specified by the test class

@RunWith(Parameterized.class)

public class java4Test {
java4 aa=new java4();
	
	String x;
	String y;

 public constructor

public java4Test(String x,String y) {
		this.x=x;//输入数据
		this.y=y;//断言数据
	}

A public static method annotated with @Parameters and contains data that needs to be tested for initialization

@Parameters
	public static Collection<Object[]>data() {
		return Arrays.asList(new Object[][]{
                //输入数据  //断言数据
				{"absesde","efsesde"},
				{"sdfcdcdcd","sdfghghgh"},
				{"sfdesfe","SFDESFE"}
		});
	}

 Test method, including assertions

@Test
	public void test() {
		String ss=aa.data(x);
		assertEquals(y, ss);
	}

 complete test code

import static org.junit.Assert.*;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.*;

import java.util.Arrays;
import java.util.Collection;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

//声明变量，测试数据和期望结果变量声明，包括测试类指定的特殊运行器部分代码
@RunWith(Parameterized.class)

public class java4Test {
java4 aa=new java4();
	
	String x;
	String y;
	
	//公共的构造函数部分
	public java4Test(String x,String y) {
		this.x=x;//输入数据
		this.y=y;//断言数据
	}
	
	//@Parameters注释的公共静态方法，并且包含初始化需要测试的数据
	@Parameters
	public static Collection<Object[]>data() {
		return Arrays.asList(new Object[][]{
				{"absesde","efsesde"},
				{"sdfcdcdcd","sdfghghgh"},
				{"sfdesfe","SFDESFE"}
		});
	}
	@Test
	public void test() {
		String ss=aa.data(x);
		assertEquals(y, ss);
	}
}

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operation result