jsp jdbc 연동에 관한 질문

HTTP Status 500 - java.lang.NullPointerException

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type Exception report

message java.lang.NullPointerException

description The server encountered an internal error that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: java.lang.NullPointerException
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:549)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:470)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

root cause

java.lang.NullPointerException
java.lang.String.(Unknown Source)
oracle.sql.CharacterSet.AL32UTF8ToString(CharacterSet.java:1517)
oracle.jdbc.driver.DBConversion.CharBytesToString(DBConversion.java:589)
oracle.jdbc.driver.DBConversion.CharBytesToString(DBConversion.java:542)
oracle.jdbc.driver.T4CTTIoauthenticate.receiveOauth(T4CTTIoauthenticate.java:816)
oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:362)
oracle.jdbc.driver.PhysicalConnection.(PhysicalConnection.java:414)
oracle.jdbc.driver.T4CConnection.(T4CConnection.java:165)
oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:35)
oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:801)
java.sql.DriverManager.getConnection(Unknown Source)
java.sql.DriverManager.getConnection(Unknown Source)
mypkg.member.SuperDao.getConnection(SuperDao.java:34)
mypkg.member.SuperDao.(SuperDao.java:26)
mypkg.member.MemberDao.(MemberDao.java:9)
org.apache.jsp.member.meList_jsp._jspService(meList_jsp.java:72)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

note The full stack trace of the root cause is available in the Apache Tomcat/7.0.42 logs.

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Apache Tomcat/7.0.42

db와 연동을 햇는데 계속 오류가 납니다. 코딩엔 문제가 없고 시스템이거나 파일이 깨진거 같은데 도저히 못찾아 질문하게되었습니다 답변좀 부탁드리겟습니다.