Java中单元测试（Junit4和Mockito）和数据库JDBC连接示例

首先添加依赖包： 保证仓库为jcenter() buildscript {     repositories {         jcenter()     }     dependencies {         classpath 'com.android.tools.build:gradle:2.3.3'         // NOTE: Do not place your application dependencies here; they belong         // in the individual module build.gradle files     } } allprojects {     repositories {          jcenter()     } } 下载jar包： dependencies {     compile fileTree(dir: 'libs', include: ['*.jar'])     androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {         exclude group: 'com.android.support', module: 'support-annotations'     })     compile 'com.android.support:appcompat-v7:26.+'     compile 'com.android.support:recyclerview-v7:26.+'     compile 'com.android.support.constraint:constraint-layout:1.0.2'     compile 'mysql:mysql-connector-java:5.+'     testCompile 'junit:junit:4.12'     testCompile 'org.mockito:mockito-all:2.+' } 测试代码： package app.hwb.com.hiaiframework; import org.junit.Before; import org.junit.Test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; import java.util.List; import static org.junit.Assert.*; import static org.mockito.Mockito.*; /**  * Example local unit test, which will execute on the development machine (host).  *  * @see <a href=" http://d.android.com/tools/testing">Testing documentation</a>  */ public class ExampleUnitTest {     public List<String> mockedList;     @Before     public void Init(){         mockedList = mock(List.class);         System.out.println("in the Init");     }     @Test     public void addition_isCorrect() throws Exception {         //Junit单元测试         assertEquals(4, 2 + 2);         //创建mock对象，参数可以是类，也可以是接口         //List<String> mockedList = mock(List.class);         mockedList.add("one");         //设置方法的预期返回值         when(mockedList.get(0)).thenReturn("hhh");         System.out.println(mockedList.size());         verify(mockedList).size();//验证方法调用（是否调用了size())         mockedList.clear();         try {             Class.forName("com.mysql.jdbc.Driver");         }catch (Exception e){             e.printStackTrace();         }         String url = "jdbc:mysql://10.12.13.88:3306/mysql";         Connection conn;         try{             conn = DriverManager.getConnection(url,"root","root");             Statement stmt = conn.createStatement();             System.out.println("Mysql数据库连接成功！");             String sql = "select * from user";             ResultSet rs = stmt.executeQuery(sql);             System.out.println("User"+"\t"+"Password");             while (rs.next()){                 System.out.print(rs.getString(2) + "\t");                 System.out.print(rs.getString(3) + "\t");                 System.out.println();             }             rs.close();             stmt.close();             conn.close();         }catch (Exception e){             e.printStackTrace();         }     } } 测试结果： in the Init 0 Mysql数据库连接成功！ User Password root *81F5E21E35407D884A6CD4A731AEBFB6AF209E1B root *81F5E21E35407D884A6CD4A731AEBFB6AF209E1B Process finished with exit code 0