例外在gwt hibernate程序中 [英] exception in gwt hibernate program

问题描述

我正在尝试制作一个简单的GWT RPC Hibernate程序，将用户添加到MySQL数据库。我正在使用Eclipse EE。该应用程序已成功将用户添加到数据库，但在编译时会引发异常。
这是异常&我的申请来源。

例外：

 线程UnitCacheLoader中的异常java.lang.RuntimeException：无法从字节缓存中读取
在com.google.gwt.dev.util.DiskCache.transferFromStream（DiskCache.java:166）
 com.google.gwt.dev.util.DiskCacheToken.readObject（DiskCacheToken.java:87）
 at sun.reflect.GeneratedMethodAccessor2.invoke（Unknown Source）
 at sun.reflect.DelegatingMethodAccessorImpl.invoke（未知源）
在java.lang.reflect.Method.invoke（未知源）
在java.io.ObjectStreamClass.invokeReadObject（未知源）
在java.io.ObjectInputStream.readSerialData（未知源）
在java.io.ObjectInputStream.readOrdinaryObject（未知源）
在java.io.ObjectInputStream.readObject0（未知源）
在java.io.ObjectInputStream.defaultReadFields（未知来源）
在java.io.ObjectInputStream.readSerialData（未知来源）
在java.io.ObjectInputStream.readOrdinaryObject（未知源）
在java.io.ObjectInputStream.readObject0（未知源）
在java.io.ObjectInputStream.readObject（未知来源）
 at com .google.gwt.dev.javac.PersistentUnitCache.loadUnitMap（PersistentUnitCache.java:493）
在com.google.gwt.dev.javac.PersistentUnitCache.access $ 000（PersistentUnitCache.java:92）
 at com.google.gwt.dev.javac.PersistentUnitCache $ UnitCacheMapLoader.run（PersistentUnitCache.java:122）
导致：java.io.StreamCorruptedException：数据块中间的意外EOF 
在java.io $ ObjectDataInputStream $ BlockDataInputStream.refill .io.InputStream.read（未知来源）
在com.google.gwt.dev.util.DiskCache.transferFromStream（DiskCache.java:154）
 ... 16更多
  

entrypoint类：

  package rpctest.client; 
 
 import rpctest.shared.FieldVerifier; 
 import com.google.gwt.core.client.EntryPoint; 
 import com.google.gwt.core.client.GWT; 
 import com.google.gwt.event.dom.client.ClickEvent; 
 import com.google.gwt.event.dom.client.ClickHandler; 
 import com.google.gwt.event.dom.client.KeyCodes; 
 import com.google.gwt.event.dom.client.KeyUpEvent; 
 import com.google.gwt.event.dom.client.KeyUpHandler; 
 import com.google.gwt.user.client.Window; 
 import com.google.gwt.user.client.rpc.AsyncCallback; 
 import com.google.gwt.user.client.ui.Button; 
 import com.google.gwt.user.client.ui.DialogBox; 
 import com.google.gwt.user.client.ui.HTML; 
 import com.google.gwt.user.client.ui.Horizo​​ntalPanel; 
 import com.google.gwt.user.client.ui.Label; 
 import com.google.gwt.user.client.ui.RootPanel; 
 import com.google.gwt.user.client.ui.TextBox; 
 import com.google.gwt.user.client.ui.VerticalPanel; 
 
 / ** 
 *入口点类定义< code> onModuleLoad（）< / code> ;. 
 * / 
 public class Rpctest实现EntryPoint {
 
 final TextBox firstName = new TextBox（）; 
 final TextBox lastName = new TextBox（）; 
 final Button ans = new Button（Add User）; 
 final label label1 = new Label（First Name）; 
 final label label2 = new Label（Last Name）; 
 // final Label errorLabel = new Label（）; 
 private VerticalPanel mainpanel = new VerticalPanel（）; 
 private Horizo​​ntalPanel addpanel1 = new Horizo​​ntalPanel（）; 
 private Horizo​​ntalPanel addpanel2 = new Horizo​​ntalPanel（）; 
 private final RpctestServiceAsync calNumbers = GWT 
 .create（RpctestService.class）; 
 
 / ** 
 *这是入口点方法。 
 * / 
 public void onModuleLoad（）{
 
 addpanel1.add（label1）; 
 addpanel1.add（firstName）; 
 addpanel2.add（label2）; 
 addpanel2.add（lastName）; 
 mainpanel.add（addpanel1）; 
 mainpanel.add（addpanel2）; 
 mainpanel.add（ans）; 
 
 ans.addClickHandler（new ClickHandler（）{
 
 @Override 
 public void onClick（ClickEvent event）{
 
 String name1 = firstName.getValue（）; 
 String name2 = lastName.getValue（）; 
 
 calNumbers.addUser（name1，name2，
 new AsyncCallback< String>（）{
 public void onFailure（Throwable catch）{
 //向用户显示RPC错误消息
 Window.alert（检查输入）; 
} 
 
 @Override 
 public void onSuccess（String result）{
 // TODO自动生成的方法stub 
 Window.alert（User is  - >+ result）; 
 } 
}）;} 
}）; 
 //我们可以向窗口小部件添加样式名称
 //sendButton.addStyleName(\"sendButton）; 
 
 //将nameField和sendButton添加到RootPanel 
 //使用RootPanel.get（）获取整个body元素
 
 /*RootPanel.get（ nameFieldContainer）添加（名称字段）。 
 * 
 RootPanel.get（sendButtonContainer）。add（sendButton）; 
 RootPanel.get（errorLabelContainer）。add（errorLabel）; * / 
 RootPanel.get（）。add（mainpanel）; 
 
} 
} 
  

strong>

  import com.google.gwt.user.client.rpc.RemoteService; 
 import com.google.gwt.user.client.rpc.RemoteServiceRelativePath; 
 
 @RemoteServiceRelativePath（testService）
 public interface RpctestService extends RemoteService {
 
 String addUser（String firstName，String lastName）throws IllegalArgumentException; 
} 
 
 
包rpctest.client; 
 
 import com.google.gwt.user.client.rpc.AsyncCallback; 
 
 public interface RpctestServiceAsync {
 
 void addUser（String firstName，String lastName，
 AsyncCallback< String> callback）; 
 
} 
  

服务实施类： / p>



  package rpctest.server; 
 
 import com.google.gwt.user.server.rpc.RemoteServiceServlet; 
 import org.hibernate.Session; 
 import org.hibernate.Transaction; 
 import hibDomain.User; 
 import rpctest.client.RpctestService; 
 
 public class RpctestServiceImpl extends RemoteServiceServlet implements RpctestService {
 
 public String addUser（String name1，String name2）
 throws IllegalArgumentException {
 
事务trns = null; 
会话session = HibernateUtil.getSessionFactory（）。openSession（）; 
 try {
 trns = session.beginTransaction（）; 
 
用户user = new User（）; 
 
 user.setFirstName（name1）; 
 user.setLastName（name2）; 
 
 session.save（user）; 
 
 session.getTransaction（）。commit（）; 
} catch（RuntimeException e）{
 if（trns！= null）{
 trns.rollback（）; 
} 
 e.printStackTrace（）; 
} finally {
 session.flush（）; 
 session.close（）; 
} 
 
 return name1; 
} 
 
} 
  

pojo类： / strong>

 包hibDomain; 
 
 public class User {
 private Integer id; 
 private String firstName; 
 private String lastName; 
 
 public Integer getId（）{
 return id; 
} 
 public void setId（Integer id）{
 this.id = id; 
} 
 public String getFirstName（）{
 return firstName; 
} 
 public void setFirstName（String firstName）{
 this.firstName = firstName; 
} 
 public String getLastName（）{
 return lastName; 
} 
 public void setLastName（String lastName）{
 this.lastName = lastName; 
} 
} 
  

映射文件 / p>



 <？xml version =1.0？> 
<！DOCTYPE hibernate-mapping PUBLIC 
 -  // Hibernate / Hibernate映射DTD 3.0 // EN
http://hibernate.sourceforge.net/hibernate-mapping-3.0 .dtd> 
 
< hibernate-mapping> 
< class name =hibDomain.Usertable =users> 
< id name =idtype =intcolumn =id> 
< generator class =native/> 
< / id> 
 
< property name =firstName> 
< column name =first_name/> 
< / property> 
< property name =lastName> 
< column name =last_name/> 
< / property> 
< / class> 
< / hibernate-mapping> 
  

cfg文件：

 <？xml version =1.0encoding =utf-8？> 
<！DOCTYPE hibernate-configuration PUBLIC 
 -  // Hibernate / Hibernate配置DTD 3.0 // EN
http://www.hibernate.org/dtd/hibernate-configuration -3.0.dtd> 
< hibernate-configuration> 
< session-factory> 
<！ - 数据库连接设置 - > 
< property name =connection.driver_class> com.mysql.jdbc.Driver< / property> 
< property name =connection.url> jdbc：mysql：// localhost / userdata< / property> 
< property name =connection.username> root< / property> 
< property name =connection.password>< / property> 
 
<！ -  JDBC连接池（使用内置） - > 
< property name =connection.pool_size> 1< / property> 
 
<！ -  SQL方言 - > 
< property name =dialect> org.hibernate.dialect.MySQLDialect< / property> 
 
<！ - 启用Hibernate的自动会话上下文管理 - > 
< property name =current_session_context_class>线程< / property> 
 
<！ - 禁用二级缓存 - > 
< property name =cache.provider_class> org.hibernate.cache.NoCacheProvider< / property> 
 
<！ - 将所有执行的SQL回显到stdout  - > 
< property name =show_sql> true< / property> 
 
<！ - 启动时删除并重新创建数据库模式 - > 
< property name =hbm2ddl.auto> update< / property> 
 
<！ - 映射文件 - > 
<映射资源=user.hbm.xml/> 
 
 
< / session-factory> 
< / hibernate-configuration> 
  

Util类：

  package rpctest.server; 
 
 import org.hibernate.SessionFactory; 
 import org.hibernate.cfg.Configuration; 
 
 public class HibernateUtil {
 private static final SessionFactory sessionFactory = buildSessionFactory（）; 
 private static SessionFactory buildSessionFactory（）{
 try {
 //从hibernate.cfg.xml创建SessionFactory 
返回新的Configuration（）。configure（）。buildSessionFactory（）; 
} 
 catch（Throwable ex）{
 //确保记录异常，因为它可能被吞下
 System.err.println（初始SessionFactory创建失败。 + ex）; 
抛出新的ExceptionInInitializerError（ex）; 
} 
} 
 public static SessionFactory getSessionFactory（）{
 return sessionFactory; 
} 
} 
  




解决方案

不太可能与磁盘空间不足有关。

更有可能您以不同的用户身份构建，或者由于其他原因，存在现有的无效临时文件导致问题。

查看您的GWT目录中的目录gwt-unitCache和报告。删除它们。然后运行蚂蚁清洁，蚂蚁测试;这应该解决问题〜

几乎可以肯定的是，它突然开始工作的原因是你做了一个像新鲜的git克隆或清除目录，删除这些文件。 ：）

I am trying to make a simple GWT RPC Hibernate program that adds a user to MySQL database. I am using Eclipse EE. The application is successfully adding user to database but it raises exception when compiled. Here is the exception & source of my application.

exception:

Exception in thread "UnitCacheLoader" java.lang.RuntimeException: Unable to read from byte cache
    at com.google.gwt.dev.util.DiskCache.transferFromStream(DiskCache.java:166)
    at com.google.gwt.dev.util.DiskCacheToken.readObject(DiskCacheToken.java:87)
    at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at java.io.ObjectStreamClass.invokeReadObject(Unknown Source)
    at java.io.ObjectInputStream.readSerialData(Unknown Source)
    at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
    at java.io.ObjectInputStream.readObject0(Unknown Source)
    at java.io.ObjectInputStream.defaultReadFields(Unknown Source)
    at java.io.ObjectInputStream.readSerialData(Unknown Source)
    at java.io.ObjectInputStream.readOrdinaryObject(Unknown Source)
    at java.io.ObjectInputStream.readObject0(Unknown Source)
    at java.io.ObjectInputStream.readObject(Unknown Source)
    at com.google.gwt.dev.javac.PersistentUnitCache.loadUnitMap(PersistentUnitCache.java:493)
    at com.google.gwt.dev.javac.PersistentUnitCache.access$000(PersistentUnitCache.java:92)
    at com.google.gwt.dev.javac.PersistentUnitCache$UnitCacheMapLoader.run(PersistentUnitCache.java:122)
Caused by: java.io.StreamCorruptedException: unexpected EOF in middle of data block
    at java.io.ObjectInputStream$BlockDataInputStream.refill(Unknown Source)
    at java.io.ObjectInputStream$BlockDataInputStream.read(Unknown Source)
    at java.io.ObjectInputStream.read(Unknown Source)
    at java.io.InputStream.read(Unknown Source)
    at com.google.gwt.dev.util.DiskCache.transferFromStream(DiskCache.java:154)
    ... 16 more

entrypoint class:

package rpctest.client;

import rpctest.shared.FieldVerifier;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.dom.client.KeyUpEvent;
import com.google.gwt.event.dom.client.KeyUpHandler;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.DialogBox;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.VerticalPanel;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
public class Rpctest implements EntryPoint {

    final TextBox firstName = new TextBox();
    final TextBox lastName = new TextBox();
    final Button ans = new Button("Add User");
    final Label label1 = new Label("First Name");
    final Label label2 = new Label("Last Name");
    //final Label errorLabel = new Label();
    private VerticalPanel mainpanel = new VerticalPanel();
    private HorizontalPanel addpanel1 = new HorizontalPanel();
    private HorizontalPanel addpanel2 = new HorizontalPanel();
    private final RpctestServiceAsync calNumbers = GWT
            .create(RpctestService.class);

    /**
     * This is the entry point method.
     */
    public void onModuleLoad() {

        addpanel1.add(label1);
        addpanel1.add(firstName);
        addpanel2.add(label2);
        addpanel2.add(lastName);
        mainpanel.add(addpanel1);
        mainpanel.add(addpanel2);
        mainpanel.add(ans);

        ans.addClickHandler(new ClickHandler() {

            @Override
            public void onClick(ClickEvent event) {

            String name1 = firstName.getValue();    
            String name2 = lastName.getValue();

            calNumbers.addUser(name1,name2,
                new AsyncCallback<String>() {
                public void onFailure(Throwable caught) {
                    // Show the RPC error message to the user
                        Window.alert("check your inputs");
                    }

                @Override
                public void onSuccess(String result) {
                // TODO Auto-generated method stub
                    Window.alert("User is ->"+result);
                }
            });}
        });
        // We can add style names to widgets
        //sendButton.addStyleName("sendButton");

        // Add the nameField and sendButton to the RootPanel
        // Use RootPanel.get() to get the entire body element

        /*RootPanel.get("nameFieldContainer").add(nameField);
         * 
        RootPanel.get("sendButtonContainer").add(sendButton);
        RootPanel.get("errorLabelContainer").add(errorLabel);*/
        RootPanel.get().add(mainpanel);

    }
}

interfaces:

import com.google.gwt.user.client.rpc.RemoteService;
import com.google.gwt.user.client.rpc.RemoteServiceRelativePath;

@RemoteServiceRelativePath("testService")
public interface RpctestService extends RemoteService {

    String addUser(String firstName,String lastName) throws IllegalArgumentException;
}


package rpctest.client;

import com.google.gwt.user.client.rpc.AsyncCallback;

public interface RpctestServiceAsync {

    void addUser(String firstName, String lastName,
            AsyncCallback<String> callback);

}

service Implementation class:

package rpctest.server;

import com.google.gwt.user.server.rpc.RemoteServiceServlet;
import org.hibernate.Session;
import org.hibernate.Transaction;
import hibDomain.User;
import rpctest.client.RpctestService;

public class RpctestServiceImpl extends RemoteServiceServlet  implements RpctestService {

        public String addUser(String name1, String name2)
            throws IllegalArgumentException {

              Transaction trns = null;
              Session session = HibernateUtil.getSessionFactory().openSession();
              try {
               trns = session.beginTransaction();

               User user = new User();

               user.setFirstName(name1);
               user.setLastName(name2);

               session.save(user);

               session.getTransaction().commit();
              } catch (RuntimeException e) {
               if(trns != null){
                trns.rollback();
               }
               e.printStackTrace();
              } finally{
               session.flush();
               session.close();
              }

            return name1; 
    }

}

pojo class:

package hibDomain;

public class User {
 private Integer id;
 private String firstName;
 private String lastName;

 public Integer getId() {
  return id;
 }
 public void setId(Integer id) {
  this.id = id;
 }
 public String getFirstName() {
  return firstName;
 }
 public void setFirstName(String firstName) {
  this.firstName = firstName;
 }
 public String getLastName() {
  return lastName;
 }
 public void setLastName(String lastName) {
  this.lastName = lastName;
 }
}

mapping file:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
 <class name="hibDomain.User" table="users" >
  <id name="id" type="int" column="id" >
   <generator class="native"/>
  </id>

  <property name="firstName">
   <column name="first_name" />
  </property>
  <property name="lastName">
   <column name="last_name"/>
  </property>
 </class>
</hibernate-mapping>

cfg file:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
 "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
 "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
 <session-factory>
  <!-- Database connection settings -->
  <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
  <property name="connection.url">jdbc:mysql://localhost/userdata</property>
  <property name="connection.username">root</property>
  <property name="connection.password"></property>

  <!-- JDBC connection pool (use the built-in) -->
  <property name="connection.pool_size">1</property>

  <!-- SQL dialect -->
  <property name="dialect">org.hibernate.dialect.MySQLDialect</property>

  <!-- Enable Hibernate's automatic session context management -->
  <property name="current_session_context_class">thread</property>

  <!-- Disable the second-level cache -->
  <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

  <!-- Echo all executed SQL to stdout -->
  <property name="show_sql">true</property>

  <!-- Drop and re-create the database schema on startup -->
  <property name="hbm2ddl.auto">update</property>

  <!-- Mapping files -->
  <mapping resource="user.hbm.xml"/>


 </session-factory>
</hibernate-configuration>

Util class:

package rpctest.server;

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

public class HibernateUtil {
 private static final SessionFactory sessionFactory = buildSessionFactory();
 private static SessionFactory buildSessionFactory() {
  try {
   // Create the SessionFactory from hibernate.cfg.xml
   return new Configuration().configure().buildSessionFactory();
  }
  catch (Throwable ex) {
   // Make sure you log the exception, as it might be swallowed
   System.err.println("Initial SessionFactory creation failed." + ex);
   throw new ExceptionInInitializerError(ex);
  }
 }
 public static SessionFactory getSessionFactory() {
  return sessionFactory;
 }
}

解决方案

This unlikely to be related to running out of disk space.

Much more likely you either built as a different user or for some other reason there are existing, invalid, temporary files which are causing the problem.

Look in your GWT dir for the directories "gwt-unitCache", and "reports". Delete them. Then run ant clean, ant test; that should solve the problem~

Almost certainly the reason it 'suddenly started worked' was you did something like a fresh git clone or cleared out the directory, deleting these files. :)

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