<jsp:useBean id="dbBean" scope="session" class="test/db/DatabaseCon"/> 这个换成
<jsp:useBean id="dbBean" scope="session" class="test.db.DatabaseCon"/>
<jsp:useBean id="dbBean" scope="session" class="test.db.DatabaseCon"/>
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package test.db;
import java.io.*;
import java.sql.*;public class DatabaseCon {
//声明类成员
public Connection con;
public String URL="jdbc:odbc:mybooks";
public String Message;
public boolean connection() {
try{
//加载JDBC-ODBC桥驱动程序
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
}
catch(ClassNotFoundException ex){
Message=ex.getMessage();
System.exit(-1);
}
try{
//试图通过JDBC-ODBC桥建立一个与mybooks数据源的连接
con = DriverManager.getConnection(URL);
return true;
}
catch(SQLException ex){
Message=ex.getMessage();
return false;
}
}
//关闭数据库连接
public boolean close(){
try{
con.close();
return true;
}
catch(Exception ex){
Message=ex.getMessage();
return false;
}
}
//执行SQL查询语句,返回执行结果集
public ResultSet exeSQL(String sqlstr){
try{
connection();
Statement stmt=con.createStatement();
ResultSet rs=stmt.executeQuery(sqlstr);
return rs;
}catch(Exception ex){
Message=ex.getMessage();
}
return null;
}
//从指定的结果集rs中返回某字段str的值
public String getString(ResultSet rs,String str){
try{
return rs.getString(str);
}catch(Exception ex){
Message=ex.getMessage();
}
return null;
}
}
<jsp:useBean id="dbBean" scope="session" class="test.db.DatabaseCon"/> 还是一样的错误!
<jsp:useBean id="dbBean" scope="session" class="test.db.DatabaseCon"/> 后,刚忘记重启tomcat了,重启后,错误变成了:
org.apache.jasper.JasperException: org.apache.jasper.JasperException: Unable to load class for JSP
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:154)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:320)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)这是什么意思
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:154)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:320)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause org.apache.jasper.JasperException: Unable to load class for JSP
org.apache.jasper.JspCompilationContext.load(JspCompilationContext.java:600)
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:142)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:320)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause java.lang.ClassNotFoundException: org.apache.jsp.testBean_jsp
java.net.URLClassLoader$1.run(Unknown Source)
java.security.AccessController.doPrivileged(Native Method)
java.net.URLClassLoader.findClass(Unknown Source)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:134)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:66)
org.apache.jasper.JspCompilationContext.load(JspCompilationContext.java:598)
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:142)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:320)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.10 logs.
总之,流程和方法肯定是对的
我怀疑是你的环境有问题,检查一下环境变量和tomcat
看看其他的能不能运行
<jsp:useBean id="dbBean" scope="session" class="test/db/DatabaseCon"/>
这里面的DatabaseCon的位置应该是指向DatabaseCon.java的位置吧?不是那个DatabaseCon.calss的位置
我最开始上CSDN的时候,第一个问题也是问关于JAVABEAN的问题原因是我在BEAN里没加public哈哈