Question

this Error shown to me.

log4j:WARN No appenders could be found for logger (org.jboss.logging).
log4j:WARN Please initialize the log4j system properly.

此错误向我显示。线程＆＃34; main＆＃34;中的例外情况org.hibernate.service.spi.ServiceException：无法创建请求的服务[org.hibernate.engine.jdbc.env.spi.JdbcEnvironment] 在org.hibernate.service.internal.AbstractServiceRegistryImpl.createService（AbstractServiceRegistryImpl.java:244）在org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService（AbstractServiceRegistryImpl.java:208） at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService（AbstractServiceRegistryImpl.java:189）在org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure（JdbcServicesImpl.java:51）在org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService（StandardServiceRegistryImpl.java:94）在org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService（AbstractServiceRegistryImpl.java:217） at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService（AbstractServiceRegistryImpl.java:189）在org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes（MetadataBuildingProcess.java:352）在org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete（MetadataBuildingProcess.java:111）在org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build（MetadataBuildingProcess.java:83）在org.hibernate.boot.internal.MetadataBuilderImpl.build（MetadataBuilderImpl.java:418）在org.hibernate.boot.internal.MetadataBuilderImpl.build（MetadataBuilderImpl.java:87）在org.hibernate.cfg.Configuration.buildSessionFactory（Configuration.java:692）在org.hibernate.cfg.Configuration.buildSessionFactory（Configuration.java:724） at conn.ConnectionUtil.getSession（ConnectionUtil.java:26）在dao.ApplicationDAO.AddCourse（ApplicationDAO.java:16）在controller.TestMain.main（TestMain.java:21）引起：org.hibernate.boot.registry.selector.spi.StrategySelectionException：无法将名称[org.hibernate.dialect.MYSQLDialect]解析为策略[org.hibernate.dialect.Dialect] at org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.selectStrategyImplementor（StrategySelectorImpl.java:113） at org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.resolveDefaultableStrategy（StrategySelectorImpl.java:162） at org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.resolveDefaultableStrategy（StrategySelectorImpl.java:126）在org.hibernate.boot.registry.selector.internal.StrategySelectorImpl.resolveStrategy（StrategySelectorImpl.java:120）在org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.constructDialect（DialectFactoryImpl.java:74）在org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect（DialectFactoryImpl.java:51）在org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService（JdbcEnvironmentInitiator.java:137） at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService（JdbcEnvironmentInitiator.java:35） at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService（StandardServiceRegistryImpl.java:88）在org.hibernate.service.internal.AbstractServiceRegistryImpl.createService（AbstractServiceRegistryImpl.java:234） ......还有16个

MY POJO CLASSES ARE

package entity;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

import org.hibernate.annotations.GenericGenerator;



@Entity
@Table(name="STUDENT")
public class Student {
    private int sid;
    private String sname;
    private long phone;
    private Course course;
    @Id
    @GenericGenerator(name="incr", strategy="org.hibernate.id.IncrementGenerator")
    @GeneratedValue(generator="incr")
    public int getSid() {
        return sid;
    }
    public void setSid(int sid) {
        this.sid = sid;
    }
    public String getSname() {
        return sname;
    }
    public void setSname(String sname) {
        this.sname = sname;
    }
    public long getPhone() {
        return phone;
    }
    public void setPhone(long phone) {
        this.phone = phone;
    }
    public Course getCourse() {
        return course;
    }
    public void setCourse(Course course) {
        this.course = course;
    }


}

Second one is

package entity;

import java.util.List;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

import org.hibernate.annotations.GenericGenerator;


@Entity
@Table(name="COURSE")
public class Course {
    private int cid;
    private String cname;
    private int fees;
    private List<Student>student;
    @Id
    @GenericGenerator(name ="incr" ,strategy="org.hibernate.Id.IncrementGenerator")
    @GeneratedValue
    public int getCid() {
        return cid;
    }
    public void setCid(int cid) {
        this.cid = cid;
    }
    public String getCname() {
        return cname;
    }
    public void setCname(String cname) {
        this.cname = cname;
    }
    public int getFees() {
        return fees;
    }
    public void setFees(int fees) {
        this.fees = fees;
    }
    public List<Student> getStudent() {
        return student;
    }
    public void setStudent(List<Student> student) {
        this.student = student;
    }


}

this is DAO class

package dao;

import org.hibernate.Session;
import org.hibernate.Transaction;

import conn.ConnectionUtil;
import entity.Course;
import entity.Student;

public class ApplicationDAO {
    private Session ses;
    private Transaction ts;
    private Course c;

    public void AddCourse(Course c){
        ConnectionUtil.getSession();
        ts = ses.beginTransaction();
        ses.save(c);
        ts.commit();
        ses.close();
    }
    public void AddStudent(Student s){
        ConnectionUtil.getSession();
        ts= ses.beginTransaction();
        ses.save(s);
        ts.commit();
        ses.close();
    }

}

This is main class

package controller;

import java.util.List;

import dao.ApplicationDAO;
import entity.Course;
import entity.Student;

public class TestMain {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Course c;
        Student s1,s2,s3;
        List<Student>ls;
        ApplicationDAO dao = new ApplicationDAO();

        c = new Course();
        c.setCname("Java");
        c.setFees(6000);
        dao.AddCourse(c);

        s1 = new Student();
        s1.setSname("Prity");
        s1.setPhone(977869543);
        s1.setCourse(c);
        dao.AddStudent(s1);

        s2 = new Student();
        s2.setSname("Rakul");
        s2.setPhone(546856);
        s2.setCourse(c);
        dao.AddStudent(s2);

        s3 = new Student();
        s3.setSname("Ajay");
        s3.setPhone(245687);
        s3.setCourse(c);
        dao.AddStudent(s3);
        System.out.println("Done");

    }

}

this is connection class

package conn;

import java.util.Properties;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

import entity.Course;
import entity.Student;

public class ConnectionUtil {
    public static Session getSession(){
        Properties p = new Properties();
        p.setProperty("hibernate.dialect", "org.hibernate.dialect.MYSQLDialect");
        p.setProperty("hibernate.connection.driver_class", "com.mysql.jdbc.Driver");
        p.setProperty("hibernate.connection.url","jdbc:mysql://localhost:3306/nilamani" );
        p.setProperty("hibernate.connection.username", "root");
        p.setProperty("hibernate.connection.password", "");
        p.setProperty("hibernate.hbm2ddl.auto", "update");
        p.setProperty("hibernate.show_sql", "true");
        p.setProperty("hibernate.format_sql", "true");

        Configuration cofig = new Configuration();
        cofig.addPackage("entities").addProperties(p).addAnnotatedClass(Course.class).addAnnotatedClass(Student.class);
        SessionFactory fac = cofig.buildSessionFactory();
        Session ses = fac.openSession();
        return ses;
    }

}`

Answer 1

方言的名称区分大小写。而不是

org.hibernate.dialect.MYSQLDialect

应该使用（小写＆＃39; y＆＃39;）：

org.hibernate.dialect.MySQLDialect

作为旁注，作为documented，此方言适用于MySQL之前的版本5.对于较新版本，有更好的选项，例如：MySQL5Dialect，MySQL5InnoDBDialect和{{3 }}

无法解析名称[org.hibernate.dialect.MYSQLDialect]

1 个答案: