价值不够？

Question

当我尝试将我的servlet代码中的数据插入到我的oracle表中时。但是我得到了以下错误，您可以将代码看作

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
* Servlet implementation class Register
*/
@WebServlet("/Register")
public class Register extends HttpServlet {
protected void doPost(HttpServletRequest request,
        HttpServletResponse response) throws ServletException, IOException {
    response.setContentType("text/html");
    PrintWriter pw = response.getWriter();

    String Name = request.getParameter("Name");
    String Email = request.getParameter("Email");
    String Password = request.getParameter("Pass");
    System.out.println("Hi");

    try {
        Class.forName("oracle.jdbc.driver.OracleDriver");
        Connection conn = DriverManager.getConnection(
                "jdbc:oracle:thin:@localhost:1521:orcl", "scott", "tiger");
        PreparedStatement ps = conn
                .prepareStatement("Insert into student values(?,?,?)");
        System.out.println("Hello");
        ps.setString(1, Name);
        ps.setString(2, Email);
        ps.setString(3, Password);

        int i = ps.executeUpdate();
        if (i > 0) {
            pw.println("Registered Successfully");
        }

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

web.xml代码如下

 <?xml version="1.0" encoding="UTF-8"?>
 <web-app >
   <display-name>Register</display-name>
 <welcome-file-list>
    <welcome-file>index.html</welcome-file>
</welcome-file-list>
<servlet>
    <servlet-name>register</servlet-name>
    <servlet-class>Register</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>register</servlet-name>
    <url-pattern>/register</url-pattern>
</servlet-mapping>

我得到的错误如下。

java.sql.SQLException: ORA-00947: not enough values

at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:112)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:331)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:288)
at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:743)
at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:213)
at oracle.jdbc.driver.T4CPreparedStatement.executeForRows(T4CPreparedStatement.java:952)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1160)
at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3285)
at oracle.jdbc.driver.OraclePreparedStatement.executeUpdate(OraclePreparedStatement.java:3368)
at Register.doPost(Register.java:40)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:646)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)

请提前帮助我解决此错误。