Access to persistence context from AbstractResource or Servlet
securez Aug 13, 2008 3:13 PMHello i have some problems getting org.jboss.seam.web.AbstractResource to work, i also try to use a pure servlet to stream data to client with the same problem.
If i stream data from filesystem no problem with both aproaches, but when i try to stream data that is stored in database (I access data trought Hibernate JPA implementation), i can't get a entity manager, i can only solve this on pure Servlet getting a EnityManagerFactory from JNDI.
So is posible to inject the persistenceContext in AbstractResource instance or pure Servlet? I try out most of the examples and nothing work.
This is my code, running on JBoss 4.2.2GA:
components.xml
<persistence:managed-persistence-context name="entityManager" auto-create="true" persistence-unit-jndi-name="java:/axudasEntityManagerFactory" />
persistence.xml
<persistence-unit name="axudas"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <jta-data-source>java:/axudasDatasource</jta-data-source> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.Oracle9Dialect"/> <property name="hibernate.hbm2ddl.auto" value="validate"/> <property name="hibernate.show_sql" value="true"/> <property name="hibernate.format_sql" value="true"/> <property name="jboss.entity.manager.factory.jndi.name" value="java:/axudasEntityManagerFactory"/> </properties> </persistence-unit>
MediaServlet.java
public class MediaServlet extends javax.servlet.http.HttpServlet implements
javax.servlet.Servlet {
static final long serialVersionUID = 1L;
/*
* (non-Java-doc)
*
* @see javax.servlet.http.HttpServlet#HttpServlet()
*/
public MediaServlet() {
super();
}
/*
* (non-Java-doc)
*
* @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest request,
* HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
response.setContentType("application/octet-stream");
response.addHeader("Content-disposition",
"attachment; filename=\"image.jpg\"");
response.addHeader("Cache-Control", "no-cache");
response.setStatus(200);
// perform JNDI lookup to obtain container-managed entity manager
EntityManager entityManager;
Context initCtx;
try {
initCtx = new InitialContext();
entityManager = ((EntityManagerFactory) initCtx
.lookup("java:axudasEntityManagerFactory")).createEntityManager();
} catch (NamingException e) {
throw new ServletException(e);
}
Prueba pb = entityManager.find(Prueba.class, 10848);
response.flushBuffer();
ServletOutputStream out = response.getOutputStream();
InputStream in;
try {
in = pb.getData().getBinaryStream();
} catch (SQLException e) {
throw new ServletException(e);
}
// FileInputStream in = new FileInputStream(new
// File("C:/Marcos/SIVSA/Download/eclipse-cpp-ganymede-win32.zip"));
byte[] buff = new byte[1024];
int nread = 0;
while ((nread = in.read(buff)) > 0) {
out.write(buff, 0, nread);
out.flush();
response.flushBuffer();
}
out.close();
in.close();
}
}MediaResource.java
@Scope(ScopeType.APPLICATION)
@Name("myResource")
@BypassInterceptors
public class Resource extends AbstractResource {
@In
private EntityManagerFactory entityManagerFactory;
@Override
public String getResourcePath() {
return "/myresource";
}
@Override
public void getResource(final HttpServletRequest request, final HttpServletResponse response)
throws ServletException, IOException {
new ContextualHttpServletRequest(request) {
@Override
public void process() throws IOException, ServletException {
response.setContentType("application/octet-stream");
response.addHeader("Content-disposition", "attachment; filename=\"image.jpg\"");
response.addHeader("Cache-Control", "no-cache");
response.setStatus(200);
response.flushBuffer();
ServletOutputStream out = response.getOutputStream();
EntityManager entityManager = entityManagerFactory.createEntityManager();
Prueba pb = entityManager.find(Prueba.class, 10848);
InputStream in;
try {
in = pb.getData().getBinaryStream();
} catch (SQLException e) {
throw new ServletException(e);
}
// FileInputStream in = new FileInputStream(new File("C:/Marcos/SIVSA/Download/eclipse-cpp-ganymede-win32.zip"));
byte[] buff = new byte[1024];
int nread = 0;
while((nread = in.read(buff)) > 0) {
out.write(buff, 0, nread);
out.flush();
response.flushBuffer();
}
out.close();
in.close();
}
}.run();
}
}So how inyect the persistence context in a clean way to AbstractResource or Servlet?
Marcos Lois