Acessando banco de dados com Servlets

oi galera…
tô pra ter um infarte…
a vários dias que tento fazer uma consulta a um banco, mando os parâmentros de um JSP para um servlet que, teoricamente, deveria conectar com o banco e fazer a consulta, maaaaaaaaaaaaas isso não ocorre. desconfio seriamente que seja um problema de configuração da aplicação até por que estou migrando essa aplicação de uma máquina para outra. agradeço deste já pela atenção. vejam os códigos e o erro:

envia.jsp

<%@page errorPage=“error.jsp” %>

ENREDO - Busca
Instituição	any institution CEFET-CE INT-EVRY PARIS VI PUC-Rio UECE UNED-CEDRO UNED-JUAZEIRO UNIV-EVRY	Language	any language English French German Italian Portuguese Spanish
Title		Delivery Mode	any mode Assynchronous Synchronous
Author		Media Type	any media Text Sound Voice Image Animation
Keywords		Agregation Level	any level Course Discipline/Bloc Unit Lesson Thema/Article Definitions/Concept
Learning Object Type	any type Narrative Text Expositive Presentation Simulation Exercise Problem Self Assessment Exam Ilustration Diagram Table Graph Example Demo

RootSearchEnredo2.java

import java.io.;
import java.util.;

import java.sql.; // JDBC
// import java.security.cert.;

import javax.servlet.<em>;      // JSDK

import javax.servlet.http.</em>;

import br.cefetce.lar.invente.EnredoBean;

public class RootSearchEnredo2 extends HttpServlet

{

Statement stmt;    // objeto para execucao do comando SQL

PreparedStatement prepStmt;

ResultSet rs;   // objeto para obtencao do resultado do comando SQL

ResultSet rsId;

Connection con;

// FormResultBean beanArray;

Vector vetor = new Vector();

static final String consultaBasica = "SELECT id, generaltitle, generalaggregationlevel, generalinstitution, generalresponsible, " +

"lifecyclecontributedate, technicalmediatype, educationallearningobjecttype from lominvente WHERE generallanguage LIKE ? "

+ "&& generalaggregationlevel LIKE ? && generalinstitution LIKE ? "

+ "&& technicalmediatype LIKE ? && technicaldeliverymode LIKE ? "

+ “&& educationallearningobjecttype LIKE ?”;

String consulta;

public void init(ServletConfig config) throws ServletException

{

super.init(config);

try
{
try
{
 Class.forName("org.gjt.mm.mysql.Driver").newInstance(); 
}
catch (Exception exception)
{ 
	
}
con = DriverManager.getConnection( "jdbc:mysql://localhost:3306/invente","root","rafael57");
//stmt = con.createStatement();
}  
catch (SQLException exception)
{
    System.out.println ("ERRO2 Servlet/JDBC> SQL Exception " + exception.getMessage());
}
} //init ===========================================================

public void doGet(HttpServletRequest req, HttpServletResponse res)

throws ServletException, IOException

{

log(req.getParameter(“showId”));

}

public void doPost(HttpServletRequest req, HttpServletResponse res)throws ServletException, IOException

{

if (!(req.getParameter(“showId”)!=null)     )

{

vetor.clear();

pesquisar(treat(req), req);

req.setAttribute(“vetor”,vetor);

RequestDispatcher rd;
rd = getServletContext().getRequestDispatcher("/jsp/enredo/ResultsSearch2.jsp");

rd.forward(req,res);

log(“dispachpu”);

}

else

{

req.setAttribute(“bean”,getById(req.getParameter(“showId”)));

RequestDispatcher rd;

rd = getServletContext().getRequestDispatcher("/jsp/enredo/ResultDetail.jsp");

rd.forward(req,res);

}

}//fim do doPost

private EnredoBean getById(String id)

{

String consulta = “SELECT * FROM lominvente WHERE id=” + id;

try

{

stmt = con.createStatement();

rsId = stmt.executeQuery(consulta);

rsId.next();

}

catch(SQLException e)

{

log("excecao no getbyid: " + e.getMessage());

}

return (makeBeanById(rsId));

}

private FormResultBean makeBean(ResultSet rs)

{

FormResultBean bean = new FormResultBean();

try

{

bean.setId(rs.getInt(“id”));

bean.setTitle(rs.getString(“generaltitle”));

bean.setAuthor(rs.getString(“generalresponsible”));

bean.setInstitution(rs.getString(“generalinstitution”));

bean.setProvisionDate(rs.getDate(“lifecyclecontributedate”));

bean.setAggregationLevel(rs.getString(“generalaggregationlevel”));

bean.setMediaType(rs.getString(“technicalmediatype”));

bean.setLearningObjectType(rs.getString(“educationallearningobjecttype”));

}

catch(SQLException ex)

{

log(“no makebean:” + ex.getMessage());

}

return bean;

}

private EnredoBean makeBeanById(ResultSet rsId)

{

EnredoBean bean = new EnredoBean();

try

{

bean.setgeneraltitle(rsId.getString(“generaltitle”));

bean.setgenerallanguage(rsId.getString(“generallanguage”));

bean.setgeneraldescription(rsId.getString(“generaldescription”));

bean.setgeneralkeywords(rsId.getString(“generalkeywords”));

bean.setgeneralaggregationlevel(rsId.getString(“generalaggregationlevel”));

bean.setgeneralinstitution(rsId.getString(“generalinstitution”));

bean.setgeneralresponsible(rsId.getString(“generalresponsible”));

bean.setgenerallocation(rsId.getString(“generallocation”));

bean.setlifecyclestatus(rsId.getString(“lifecyclestatus”));

bean.setlifecycleversion(rsId.getString(“lifecycleversion”));

bean.setlifecyclecontributedate(rsId.getDate(“lifecyclecontributedate”).toString());

bean.setmetametadatacontributeentity(rsId.getString(“metametadatacontributeentity”));

bean.setmetametadatacontributerole(rsId.getString(“metametadatacontributerole”));

bean.setmetametadatametadatascheme(rsId.getString(“metametadatametadatascheme”));

bean.setmetametadatalanguage(rsId.getString(“metametadatalanguage”));

bean.setmetametadataauthoningtool(rsId.getString(“metametadataauthoningtool”));

bean.setmetametadatacontributeemail(rsId.getString(“metametadatacontributeemail”));

bean.settechnicaldeliverymode(rsId.getString(“technicaldeliverymode”));

bean.settechnicalmediatype(rsId.getString(“technicalmediatype”));

bean.settechnicalformat(rsId.getString(“technicalformat”));

bean.settechnicalsize(rsId.getString(“technicalsize”));

bean.settechnicalrequirementsoperatingsystem(rsId.getString(“technicalrequirementsoperatingsystem”));

bean.settechnicalrequirementsbrowser(rsId.getString(“technicalrequirementsbrowser”));

bean.settechnicalrequirementsapplication(rsId.getString(“technicalrequirementsapplication”));

bean.settechnicalrequirementsnetwork(rsId.getString(“technicalrequirementsnetwork”));

bean.settechnicalrequirementslink(rsId.getString(“technicalrequirementslink”));

bean.settechnicalrequirementsduration(rsId.getString(“technicalrequirementsduration”));

bean.seteducationallearningobjecttype(rsId.getString(“educationallearningobjecttype”));

bean.seteducationaltypicallearningtime(rsId.getString(“educationaltypicallearningtime”));

bean.setrelationkind(rsId.getString(“relationkind”));

bean.setrelationobjectreference(rsId.getString(“relationobjectreference”));

bean.setrelationobjectname(rsId.getString(“relationobjectname”));

bean.setrelationdescription(rsId.getString(“relationdescription”));

bean.setrightscopyright(rsId.getString(“rightscopyright”));

bean.setrightscomments(rsId.getString(“rightscomments”));

}

catch(SQLException ex)

{

log(“no makebean:” + ex.getMessage());

}

return bean;

}

private ArrayList treat(HttpServletRequest req)

{

ArrayList elementos = new ArrayList();

String connector = req.getParameter(“connector”);

consulta = consultaBasica;

elementos.add(manipulateTitle(req));

elementos.add(manipulateKeyWords(req));

// elementos.add(manipulateEducationalObjective(req));

elementos.add(manipulateAuthor(req));

log(“kjfkjjfhvj”);

log(consulta);

return (elementos);

}

private String[] manipulateTitle(HttpServletRequest req)

{

StringBuffer queryString  = new StringBuffer(req.getParameter(“title”));

String consultaBasicaAdd  = "&& generaltitle LIKE ? ";

String strRetorno[] = null;

if (!(req.getParameter(“title”).equals("")))
{

if (((queryString.charAt(0)==’"’) && (queryString.charAt(queryString.length()-1)==’"’))

|| ((queryString.charAt(0)==’’’) && (queryString.charAt(queryString.length()-1)==’’’)))

{

strRetorno = treatPhrase(queryString, consultaBasicaAdd);

}  //fim do if ((queryString.charAt(0)==’"’) && (queryString.charAt(queryString.length()-1))==’"’)

else

{

strRetorno = treatWords(queryString, consultaBasicaAdd);

} //fim do else if ((queryString.charAt(0)==’"’) && (queryString.charAt(queryString.length()-1))==’"’)

return (strRetorno);

}

else

{

consulta += consultaBasicaAdd;

return (new String[] {"%"});

}

}//fim do manipulateTitle()

private String[] manipulateKeyWords(HttpServletRequest req)

{

String consultaBasicaAdd  = "&& generalkeywords LIKE ? ";

if (!(req.getParameter(“keywords”).equals("")))

{

StringBuffer queryString  = new StringBuffer(req.getParameter(“keywords”));

String strRetorno[] = null;

strRetorno = treatWords(queryString, consultaBasicaAdd);

return (strRetorno);

}

else

{

consulta += consultaBasicaAdd;

return (new String[] {"%"});

}

}//fim do manipulateKeyWords()

private String[] manipulateAuthor(HttpServletRequest req)

{

String consultaBasicaAdd  = "&& generalresponsible LIKE ? ";

if (!(req.getParameter(“responsible”).equals("")))

{

StringBuffer queryString  = new StringBuffer(req.getParameter(“responsible”));

String strRetorno[] = null;

strRetorno = treatWords(queryString, consultaBasicaAdd);

return (strRetorno);

}

else

{

consulta += consultaBasicaAdd;

return (new String[] {"%"});

}

}//fim do manipulateKeyWords()

/*

private String[] manipulateEducationalObjective(HttpServletRequest req)

{

StringBuffer queryString  = new StringBuffer(req.getParameter(“edobjective”));

String consultaBasicaAdd  = "&& educationaldescription LIKE ? ";

String strRetorno[] = null;

if (!(req.getParameter(“edobjective”).equals("")))

{

if (((queryString.charAt(0)==’"’) && (queryString.charAt(queryString.length()-1)==’"’))

|| ((queryString.charAt(0)==’’’) && (queryString.charAt(queryString.length()-1)==’’’)))

{

strRetorno = treatPhrase(queryString, consultaBasicaAdd);

}  //fim do if ((queryString.charAt(0)==’"’) && (queryString.charAt(queryString.length()-1))==’"’)

else

{

strRetorno = treatWords(queryString, consultaBasicaAdd);

} //fim do else if ((queryString.charAt(0)==’"’) && (queryString.charAt(queryString.length()-1))==’"’)

return (strRetorno);

}

else

{

consulta += consultaBasicaAdd;

return (new String[] {"%"});

}

}//fim do manipulateEducationalObjective()

*/

private void pesquisar(ArrayList elem,HttpServletRequest req)

{

int param = 1;

try

{

consulta += “;”;

prepStmt = con.prepareStatement(consulta);

prepStmt.setString(param++,req.getParameter(“language”));

prepStmt.setString(param++,req.getParameter(“aggregation”));

prepStmt.setString(param++,req.getParameter(“institution”));

prepStmt.setString(param++,req.getParameter(“mediatype”));

prepStmt.setString(param++,req.getParameter(“deliverymode”));

prepStmt.setString(param++,req.getParameter(“learningobjecttype”));

for(int i=0;i<elem.size();i++)

{

String temp[] = (String []) elem.get(i);

for(int k=0;k<temp.length;k++)
 {
   
  prepStmt.setString(param++,temp[k]);
  log(temp[k]); 
 } 
}
rs = prepStmt.executeQuery();
  
for(int i=0;rs.next();i++)
{
 vetor.addElement(makeBean(rs));
}

}//fim do try

catch(SQLException e)

{

System.err.println(e.getMessage());

}//fim do catch

finally

{

try

{

prepStmt.clearParameters();

}

catch (SQLException e)

{

e.printStackTrace();

}

try

{

if ( rs != null )

{

rs.close();

}

}

catch (SQLException e)

{

e.printStackTrace();

}

}//fim do finally

}

private String[] treatPhrase(StringBuffer queryString, String consultaBasicaAdd)

{

queryString.setCharAt(0,’%’);

queryString.setCharAt(queryString.length()-1,’%’);

consulta += consultaBasicaAdd;

return (new String[] {queryString.toString()});

}//fim do método String[] treatPhrase(StringBuffer queryString, String consultaBasicaAdd)

private String[] treatWords(StringBuffer queryString, String consultaBasicaAdd)

{

String separador = “”;

StringTokenizer queryStringTokenizer = new StringTokenizer("");

boolean umaPalavra = false;

if (queryString.toString().indexOf(’ ‘)>=0)

{

separador = " ";

queryStringTokenizer = new StringTokenizer(queryString.toString(),separador);

}

else

if (queryString.toString().indexOf(’,’)>=0)

{

separador = “,”;

queryStringTokenizer = new StringTokenizer(queryString.toString(),separador);

}

else

umaPalavra = true;

//numero de palavras digitadas pelo usuario

int numPalavras = 0;

if (umaPalavra)

numPalavras = 1;

else

numPalavras = queryStringTokenizer.countTokens();

String palavras[] = new String[numPalavras];

for(int i=0;i<numPalavras;i++)

{

if (umaPalavra)

{

queryString = queryString.insert(0,’%’);

queryString = queryString.append(’%’);

palavras[i] = queryString.toString();

consulta += consultaBasicaAdd;

break;

}

StringBuffer item = new StringBuffer(queryStringTokenizer.nextToken());
item = item.insert(0,'%');
item = item.append('%');

palavras[i] = item.toString();
log(palavras[i]);
consulta += consultaBasicaAdd;
log(consulta);

}//fim do  for(int i=0;i<numPalavras;i++)

return palavras;

}

}

erro.tomcat

HTTP Status 500 -

type Exception report

message

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

exception

java.lang.NullPointerException

RootSearchEnredo2.pesquisar(RootSearchEnredo2.java:323)

RootSearchEnredo2.doPost(RootSearchEnredo2.java:63)

javax.servlet.http.HttpServlet.service(HttpServlet.java:709)

javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

org.apache.catalina.servlets.InvokerServlet.serveRequest(InvokerServlet.java:419)

org.apache.catalina.servlets.InvokerServlet.doPost(InvokerServlet.java:169)

javax.servlet.http.HttpServlet.service(HttpServlet.java:709)

javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.
Apache Tomcat/5.5.17

ENREDO - Busca

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