0

我有一个这样设置的数据库

  CREATE TABLE item (             
              ItemID int(11) NOT NULL auto_increment,  
              ItemName char(25),      
              YearManufactured int(11),   
              CopiesSold int(11),
              AmountInStock int(11),
              image blob,                         
              Description char(30),     
              PRIMARY KEY  (`ItemID`)                   
     );

该表工作正常,我已经能够很好地插入和删除它。我想组织我的代码有点不同,并使用 Java 而不是编写脚本来更新表。我想切换到这样做的最初原因是因为我希望能够更轻松地上传图像。这是我的代码:

这是最初打开的脚本。URL、UserID 和 Password 绝对正确。

<%  
    // Instantiating the connection to the database
    String mysJDBCDriver = "com.mysql.jdbc.Driver"; 
    String mysURL = "MY_ADDRESS"; 
    String mysUserID = "USERNAME"; 
    String mysPassword = "PASSWORD";

    java.sql.Connection conn=null; // a new connection
    try 
    {
        DB db = new DB();
        conn=db.dbConnect(mysJDBCDriver, mysURL,mysUserID,mysPassword);
        db.insertImage(conn,"c:/Users/DPiganell/image_launch_a5.jpg");
        db.getImageData(conn);
        System.out.println("Connected successfully to database using JConnect");
        session.setAttribute("connection", conn);

     }
    catch(Exception e)
    {
        e.printStackTrace();
        out.print(e.toString());
    }

%>

这是我的数据库对象

package DBPackage;

import java.io.*;
import java.sql.*;

public class DB
{
        public DB() {}

        public Connection dbConnect(String db_driver, String db_connect_string,
           String db_userid, String db_password)
        {
                try
                {
                        Class.forName(db_driver);
                        Connection conn = DriverManager.getConnection(
                          db_connect_string, db_userid, db_password);

                        System.out.println("connected");
                        return conn;

                }
                catch (Exception e)
                {
                        e.printStackTrace();
                        return null;
                }
        }

        public void insertImage(Connection conn,String img)
        {
                int len;
                String query;
                PreparedStatement pstmt;

                try
                {
                        File file = new File(img);
                        FileInputStream fis = new FileInputStream(file);
                        len = (int)file.length();

//                        query = ("UPDATE item SET image = ? WHERE ItemID = ?");
                        query = ("INSERT INTO ITEM (ItemType, ItemName, YearManufactured, CopiesSold, AmountInStock, image, description) "
                    + "VALUES(?,?,?,?,?,?,?");
                        pstmt = conn.prepareStatement(query);
                        pstmt.setString(1, "DVD");
                        pstmt.setString(2, "fsd");
                        pstmt.setInt(3, 1991);
                        pstmt.setInt(4, 6);
                        pstmt.setInt(5, 7);
                        pstmt.setString(7, "works");

                        // Method used to insert a stream of bytes
                        pstmt.setBinaryStream(6, (InputStream)fis, len);
                        pstmt.executeUpdate();

                }
                catch (SQLException e)
                {
                        e.printStackTrace();
                }
                catch (Exception e)
                {
                        e.printStackTrace();
                }
        }

        public void getImageData(Connection conn)
        {

                 byte[] fileBytes;
                 String query;
                 try
                 {
                         query = "select image from item where ItemID=3";
                         Statement state = conn.createStatement();
                         ResultSet rs = state.executeQuery(query);
                         if (rs.next())
                        {
                                  fileBytes = rs.getBytes(1);
                                  OutputStream targetFile=  
                                  new FileOutputStream(
                                       "C:/Users/DPiganell/newImage.jpg");

                                  targetFile.write(fileBytes);
                                  targetFile.close();
                        }        

                 }
                 catch (Exception e)
                 {
                         e.printStackTrace();
                 }
        }
};

一旦程序到达executeUpdate,就会抛出异常。任何帮助表示赞赏。如果它更容易,我愿意采取不同的方法。

SQLException 堆栈跟踪:

SEVERE: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
    at com.mysql.jdbc.Util.getInstance(Util.java:386)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1053)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4096)
    at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4028)
    at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2490)
    at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2651)
    at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2734)
    at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2458)
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2375)
    at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2359)
    at DBPackage.DB.insertImage(DB.java:55)
    at org.apache.jsp.header_jsp._jspService(header_jsp.java:61)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:403)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:492)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
    at org.apache.catalina.core.ApplicationDispatcher.doInvoke(ApplicationDispatcher.java:787)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:649)
    at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:604)
    at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:534)
    at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:1015)
    at org.apache.jsp.index_jsp._jspService(index_jsp.java:60)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:403)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:492)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
    at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:722)

SEVERE:     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
SEVERE:     at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
SEVERE:     at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
SEVERE:     at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
SEVERE:     at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
SEVERE:     at com.mysql.jdbc.Util.getInstance(Util.java:386)
SEVERE:     at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1053)
SEVERE:     at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4096)
SEVERE:     at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4028)
SEVERE:     at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2490)
SEVERE:     at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2651)
SEVERE:     at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2734)
SEVERE:     at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
SEVERE:     at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2458)
SEVERE:     at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2375)
SEVERE:     at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:2359)
SEVERE:     at DBPackage.DB.insertImage(DB.java:55)
SEVERE:     at org.apache.jsp.header_jsp._jspService(header_jsp.java:61)
SEVERE:     at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
SEVERE:     at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
SEVERE:     at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:403)
SEVERE:     at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:492)
SEVERE:     at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
SEVERE:     at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
SEVERE:     at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
SEVERE:     at org.apache.catalina.core.ApplicationDispatcher.doInvoke(ApplicationDispatcher.java:787)
SEVERE:     at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:649)
SEVERE:     at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:604)
SEVERE:     at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:534)
SEVERE:     at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:1015)
SEVERE:     at org.apache.jsp.index_jsp._jspService(index_jsp.java:60)
SEVERE:     at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
SEVERE:     at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
SEVERE:     at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:403)
SEVERE:     at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:492)
SEVERE:     at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
SEVERE:     at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
SEVERE:     at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
SEVERE:     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
SEVERE:     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
SEVERE:     at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
SEVERE:     at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
SEVERE:     at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
SEVERE:     at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
SEVERE:     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
SEVERE:     at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
SEVERE:     at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
SEVERE:     at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
SEVERE:     at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
SEVERE:     at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
SEVERE:     at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
SEVERE:     at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
SEVERE:     at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
SEVERE:     at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
SEVERE:     at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
SEVERE:     at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
SEVERE:     at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
SEVERE:     at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
SEVERE:     at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
SEVERE:     at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
SEVERE:     at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
SEVERE:     at java.lang.Thread.run(Thread.java:722)
4

1 回答 1

0

您的查询语法看起来错误,请检查左括号和右括号。

于 2012-11-28T02:15:49.707 回答