老师帮忙看一下代码，运行不出来

 driverClass=com.mysql.js.jdbc.Driver;
 url = mysql:jdbc:///jdbc?useSSL=false&serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf-8;
 user=root;
 password=marryme533;

package com.imooc.utils;

import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

/*
 * JDBC的工具类
 * 
 * */
public class JDBCUtils {
	private static final String driverClass;
	private static final String url;
	private static final String user;
	private static final String password;
	
	static {
		//加载属性文件并解析
		Properties props = new Properties();
		//如何获得属性文件的输入流
		//通常情况下使用类的加载器的方式进行获取
		InputStream is = JDBCUtils.class.getClassLoader().getResourceAsStream("jdbc.properties");
		try {
			props.load(is);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		driverClass = props.getProperty("driverClass");
		url = props.getProperty("url");
		user = props.getProperty("user");
		password = props.getProperty("password");
	}
	/*
	 * 注册驱动的方法
	 * 
	 * */
	public static void loadDriver() throws ClassNotFoundException {
		Class.forName(driverClass);
	}
	/*
	 * 获得连接的方法
	 */
	public static Connection getConnection() throws Exception {
		loadDriver();
		Connection conn = DriverManager.getConnection(url, user, password);
		return conn;
	}
	/*
	 * 资源释放
	 */
	public static void release(Statement stmt,Connection conn) {
		if(stmt != null) {
			try {
				stmt.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			stmt=null;
		}
		if(conn != null) {
			try {
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			conn=null;
		}
	}
	public static void realease(ResultSet rs,Statement stmt,Connection conn) {
		if(stmt != null) {
			try {
				stmt.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			stmt=null;
		}
		if(conn != null) {
			try {
				conn.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			conn=null;
		}
		if(rs != null) {
			try {
				rs.close();
			}catch(SQLException e) {
				e.printStackTrace();
			}
			rs=null;
		}
	}
}

package com.imooc.jdbc;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;

import org.junit.Test;

import com.imooc.utils.JDBCUtils;

/*
 * preparedStatemnet的使用
 */
public class JDBCDeno3 {
	@Test
	public void test3() {
		Connection conn = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		try {
			conn = JDBCUtils.getConnection();
			String sql="select * from goods";
			pstmt = conn.prepareStatement(sql);
			rs = pstmt.executeQuery();
			while(rs.next()) {
				System.out.println(rs.getString("name"));
			}
		}catch(Exception e) {
			e.printStackTrace();
		}finally {
			JDBCUtils.realease(rs, pstmt, conn);
		}
	}
	@Test
	public void demo3() {
		Connection conn = null;
		PreparedStatement pstmt = null;
		ResultSet rs = null;
		try {
			//建立连接
			conn = JDBCUtils.getConnection();
			String sql="insert into goods values (null,?,?,?)";
			pstmt = conn.prepareStatement(sql);
			pstmt.setString(1, "微波炉");
			//pstmt.setString(2, "200.0");
			pstmt.setString(3, "方便");
			pstmt.executeUpdate();
			rs = pstmt.executeQuery("select * from goods");
			while(rs.next()) {
				System.out.println(rs.getString("id"+"   "+rs.getString("name")+"   "+rs.getFloat("price")));
			}
			
		}catch(Exception e) {
			e.printStackTrace();
		}finally {
			//释放资源
			JDBCUtils.realease(rs, pstmt, conn);
		}
	}
}

报错：

java.lang.NoClassDefFoundError: Could not initialize class com.imooc.utils.JDBCUtils

at com.imooc.jdbc.JDBCDeno3.demo3(JDBCDeno3.java:59)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.lang.reflect.Method.invoke(Unknown Source)

at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)

at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)

at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)

at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)

at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)

at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)

at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)

at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)

at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)

at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)

at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)

at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)

at org.junit.runners.ParentRunner.run(ParentRunner.java:363)

at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)

at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206)