Object database for Java
I've recently got interested in object databases and would like to do my next project using ODB instead of a relational one. Now, since I'm completely new to them, it would be helpful if someone could recommend one to me. Can ODBs be queried with SQL or do they use a different system?
Please, don't be mad about this type of (barely-java-related) question. I did do some googling and discovered a few useful things (ie db4o), but I'd like a recommendation since I need something easy to adopt as I've alreadu started coding my project.
jadespirit wrote:
I've recently got interested in object databases and would like to do my next project using ODB instead of a relational one. Why? Resume building, or is there a technical reason for this decision?
What do you know today about ODBs?
Now, since I'm completely new to them, it would be helpful if someone could recommend one to me. Can ODBs be queried with SQL or do they use a different system?
Not with SQL.
Please, don't be mad about this type of (barely-java-related) question. I did do some googling and discovered a few useful things (ie db4o), but I'd like a recommendation since I need something easy to adopt as I've alreadu started coding my project.db4o is a fine place to start.
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Usage of Object Cache for Java in J2EE apps
Hi,
we are investigating on whether we can use the Object Cache for Java
(OCS4J) for our requirements. The question we have come across is:
What is the designated way of integration for the Object cache to fit
into the J2EE environment? Unfortunately, although the current manuals
group OCS4J into the "Oracle Containers for J2EE Services Guide" and the
suggested package name for the whole thing in JSR 107 seems to be
javax.util.jcache, there is very little documentation on how the
designers would like J2EE programmers to use the cache from within a
J2EE app and all examples given are not from within a J2EE environment.
We are in particular thinking about a hierarchy of several cache
"compartments" (Region->Subregion->group) for different topics and using
the hierarchical name of the cache (region.subregion.group) as the
primary key for BMP Entity beans, each of them having their own
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the appropriate Entity Bean with the Cache Access object and then do the
required operations on the cache.
But then we immediately run into the question of how the mapping between
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Thanks in advance for any help!
Andreas Loew
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Regards
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Javax.naming.NameNotFoundException: No object bound for java:comp/env/...
Help, help! I have a problem:
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at com.sun.enterprise.naming.java.javaURLContext.lookup(javaURLContext.java:116)
at com.sun.enterprise.naming.java.javaURLContext.lookup(javaURLContext.java:127)
at javax.naming.InitialContext.lookup(InitialContext.java:355)
at oracle.toplink.jndi.JNDIConnector.connect(Unknown Source)
at oracle.toplink.sessions.DatabaseLogin.connect(Unknown Source)
at oracle.toplink.internal.databaseaccess.DatabaseAccessor.connect(Unknown Source)
at oracle.toplink.internal.databaseaccess.DatabaseAccessor.connect(Unknown Source)
at oracle.toplink.threetier.ConnectionPool.buildConnection(Unknown Source)
at oracle.toplink.threetier.ConnectionPool.startUp(Unknown Source)
at oracle.toplink.threetier.ServerSession.connect(Unknown Source)
at oracle.toplink.publicinterface.DatabaseSession.login(Unknown Source)
at oracle.toplink.tools.sessionmanagement.SessionManager.getSession(Unknown Source)
at oracle.toplink.tools.sessionmanagement.SessionManager.getSession(Unknown Source)
at com.configurator.datasource.ToplinkClientSessionManager.<init>(ToplinkClientSessionManager.java:18)
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at com.configurator.ConfiguratorServiceMediatorImpl.getModelsFromDB(ConfiguratorServiceMediatorImpl.java:3
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.axis.providers.java.RPCProvider.invokeMethod(RPCProvider.java:384)
at org.apache.axis.providers.java.RPCProvider.processMessage(RPCProvider.java:281)
at org.apache.axis.providers.java.JavaProvider.invoke(JavaProvider.java:319)
at org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:32)
at org.apache.axis.SimpleChain.doVisiting(SimpleChain.java:118)
at org.apache.axis.SimpleChain.invoke(SimpleChain.java:83)
at org.apache.axis.handlers.soap.SOAPService.invoke(SOAPService.java:450)
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at org.apache.axis.transport.http.AxisServlet.doPost(AxisServlet.java:653)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
at org.apache.axis.transport.http.AxisServletBase.service(AxisServletBase.java:301)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at com.evermind.server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java:765)
at com.evermind.server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java:317)
at com.evermind.server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java:790)
at com.evermind.server.http.HttpRequestHandler.run(HttpRequestHandler.java:270)
at com.evermind.server.http.HttpRequestHandler.run(HttpRequestHandler.java:112)
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code:
initialContext = new InitialContext();
LocalStatelessREHome localHome = (LocalStatelessREHome)initialContext.lookup("java:comp/env/StatelessREBean");
in web.xml:
<ejb-local-ref>
<ejb-ref-name>StatelessREBean</ejb-ref-name>
<ejb-ref-type>Session</ejb-ref-type>
<local-home>com.re.stateless.ejb.LocalStatelessREHome</local-home>
<local>com.re.stateless.ejb.LocalStatelessRE</local>
<ejb-link>StatelessREBean</ejb-link>
</ejb-local-ref>
Any help will be appreciated! Thanks in advance.Try removing the JNDI fully qualified name (i.e. java:comp\env\) Use the name of your bean to lookup.
It worked for me when i used to get a similar exception. -
How to Cache Data from database for java mapping ?
Hi
I have a scenario where i have to dynamically query a huge table in some other database from java mapping code.
Therefore instead of making a new Database trip everytime is there a mechanism by which i can cache the entire table contents into XI first and then use this cache for looking up data through my java mapping.
Any other alternative also welcome which would give best performance.
Please Suggest
regards
Nilesh Taunk.Hi Nilesh,
I am not sure if you can actually cache the table in XI. You will have to look up directly from your Database everytime your mapping excecutes.
To perform DB lookup during mapping very efficiently, I would suggest that you take a look at this blog,
/people/siva.maranani/blog/2005/08/23/lookup146s-in-xi-made-simpler
Also, instead of doing the DB look up in mapping, you can also use your JDBC adapter as a sender and collect the information you want from your DB,
If you are using your JDBC as a sender, then your JDBC will poll over your database and select the rows that satisfy your Select Query. Also, there is another field in your JDBC adapter that is very important and that is the Update satatement. Once your JDBC adapter executes your select query and selects rows from the database, you might not need those rows to be selected again. In this csse, you can use the Update statement to update the database.
http://help.sap.com/saphelp_nw04/helpdata/en/7e/5df96381ec72468a00815dd80f8b63/content.htm
http://help.sap.com/saphelp_nw04/helpdata/en/2e/96fd3f2d14e869e10000000a155106/content.htm
The choice between a JDBC sender adapter , and the DB lookup will have to be on the basis of your requirements.
Regards,
Bhavesh -
XML to Object Mapping for Java Enums
Hi,
I have a question regarding XmlBeans. Does tangosol XmlBean support Java Enums for managing XML-to-Object mapping? If so, is there any documentation/examples?... and I'm back. XmlBean does not support Java enum types.
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Database access tool for Java Development
Hi,
A couple of days back, our SAP's database (MSSQL) was corrupted and downed the Java Stack.
During the Java development, normally after a newly created table was deployed via Java Dictionary, Java developer will access the database via the MSSQL Enterprise Manager to view/delete/update data. Unlike the ABAP development, all database access was done via SE16 in SAPGUI. It was believed that the Java Development kind of direct access to the database via the MSSQL Enterprise Manager was causing some MSSQL tables to be corrupted, and thus downed the Java Stack.
1. Is there any tool like SE16 to access database during the Java Development?
2. If no, what kind of recommendation/tool to access database for Java Development?
Any help would be much appreciated. Thanks.
juliusJulius,
There are no industry recommended open source DB tools.
Normally it depends upon the developer preferences that how he/she wants to see the tool usability.
I can suggest you to go through the below link:
http://sourceforge.net/search/?type_of_search=soft&words=SQL+Tools
You can find many open source SQL tools, which you have to test and select one among them.
I can suggest you to use:
1) TOra
2) Easy SQL
3) SQuirrel
"Choose a Tool which is easy to use and efficient, Dont worry about Look n Feel"
Best of Luck -
Parser for Java v2 decimal formatting bug
XML Parser for Java v2 (up to 2.0.2.7) does not seem to format decimal numbers correctly with format-number() function. It can handle floats, but not doubles. When can this bug get fixed?
BTW, is there a bug database for Java XML Parser?
Thanks,
nullThanks for your prompt response, here is one test:
format.xml:
<?xml version="1.0"?>
<numberlist>
<number>1234567.123456789</number>
<number>12345678.123456789</number>
<number>123456789.123456789</number>
</numberlist>
format.xsl:
<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:template match="number">
<xsl:value-of select="format-number(current(), '#,##0.00000000')"/>
</xsl:template>
</xsl:stylesheet>
The following output was generated from 2.0.2.7:
<?xml version = '1.0' encoding = 'UTF-8'?>
1,234,567.12500000
12,345,678.00000000
123,456,792.00000000
Apache Xalan 0.20 generates the following:
<?xml version="1.0" encoding="UTF-8"?>
1,234,567.12345679
12,345,678.12345679
123,456,789.12345679
This problem also exists in v2 versions before 2.0.2.7.
A month ago, I posted another bug report, but didn't get any reponse. Can someone look into the problem? I suspect XMLElement.setAttribute(name, value) doesn't add attributes of ID type to the internal list of ID's. The posting is at:
http://technet.oracle.com:89/ubb/Forum11/HTML/000994.html
Thanks,
null -
Java.lang.VerifyError - Incompatible object argument for function call
Hi all,
I'm developing a JSP application (powered by Tomcat 4.0.1 in JDK 1.3, in Eclipse 3.3). Among other stuff I have 3 classes interacting with an Oracle database, covering 3 use cases - renaming, adding and deleting an database object. The renaming class simply updates the database with a String variable it receives from the request object, whereas the other two classes perform some calculations with the request data and update the database accordingly.
When the adding or deleting classes are executed, by performing the appropriate actions through the web application, Tomcat throws the following:
java.lang.VerifyError: (class: action/GliederungNewAction, method: insertNewNode signature: (Loracle/jdbc/driver/OracleConnection;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;I)V) Incompatible object argument for function call
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:120)
at action.ActionMapping.perform(ActionMapping.java:53)
at ControllerServlet.doResponse(ControllerServlet.java:92)
at ControllerServlet.doPost(ControllerServlet.java:50)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
...The renaming works fine though. I have checked mailing lists and forums as well as contacted the company's java support but everything I have tried out so far, from exchanging the xerces.jar files found in JDOM and Tomcat to rebuidling the project didn't help.
I just can't explain to myself why this error occurs and I don't see how some additional Java code in the other 2 classes could cause it?
I realize that the Tomcat and JDK versions I'm using are totally out of date, but that's company's current standard and I can't really change that.
Here's the source code. I moved parts of the business logic from Java to Oracle recently but I left the SQL statements that the Oracle stored procedures are executing if it helps someone.
package action;
import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.StringTokenizer;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import oracle.jdbc.driver.OracleConnection;
* This class enables the creation and insertion of a new catalogue node. A new node
* is always inserted as the last child of the selected parent node.
public class GliederungNewAction implements Action {
public String perform(ActionMapping mapping, HttpServletRequest request,
HttpServletResponse response) {
// fetch the necessary parameters from the JSP site
// the parent attribute is the selected attribute!
String parent_attribute = request.getParameter("attr");
String catalogue = request.getParameter("catalogue");
int parent_sequenceNr = Integer.parseInt(request.getParameter("sort_sequence"));
// connect to database
HttpSession session = request.getSession();
db.SessionConnection sessConn = (db.SessionConnection) session.getAttribute("connection");
if (sessConn != null) {
try {
sessConn.setAutoCommit(false);
OracleConnection connection = (OracleConnection)sessConn.getConnection();
int lastPosition = getLastNodePosition( getLastChildAttribute(connection, catalogue, parent_attribute) );
String newNodeAttribute = createNewNodeAttribute(parent_attribute, lastPosition);
// calculate the sequence number
int precedingSequenceNumber = getPrecedingSequenceNumber(connection, catalogue, parent_attribute);
if ( precedingSequenceNumber == -1 ) {
precedingSequenceNumber = parent_sequenceNr;
int sortSequence = precedingSequenceNumber + 1;
setSequenceNumbers(connection, catalogue, sortSequence);
// insert the new node into DB
insertNewNode(connection, catalogue, newNodeAttribute, parent_attribute, "Neuer Punkt", sortSequence);
connection.commit();
} catch(SQLException ex) {
ex.printStackTrace();
return mapping.getForward();
* Creates, fills and executes a prepared statement to insert a new entry into the specified table, representing
* a new node in the catalogue.
private void insertNewNode(OracleConnection connection, String catalogue, String attribute, String parent_attribute, String description, int sortSequence) {
try {
String callAddNode = "{ call fasi_lob.pack_gliederung.addNode(:1, :2, :3, :4, :5) }";
CallableStatement cst;
cst = connection.prepareCall(callAddNode);
cst.setString(1, catalogue);
cst.setString(2, attribute);
cst.setString(3, parent_attribute);
cst.setString(4, description);
cst.setInt(5, sortSequence);
cst.execute();
cst.close();
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
// String insertNewNode = "INSERT INTO vstd_media_cat_attributes " +
// "(catalogue, attribute, parent_attr, description, sort_sequence) VALUES(:1, :2, :3, :4, :5)";
// PreparedStatement insertStmt;
// try {
// insertStmt = connection.prepareStatement(insertNewNode);
// insertStmt.setString(1, catalogue);
// insertStmt.setString(2, attribute);
// insertStmt.setString(3, parent_attribute);
// insertStmt.setString(4, description);
// insertStmt.setInt(5, sortSequence);
// insertStmt.execute();
// insertStmt.close();
// } catch (SQLException e) {
// e.printStackTrace();
* This method returns the attribute value of the last child of the parent under which
* we want to insert a new node. The result set is sorted in descending order and only the
* first result (that is, the last child under this parent) is fetched.
* If the parent node has no children, "parent_attr.0" is returned.
* @param connection
* @param catalogue
* @param parent_attribute
* @return attribute of the last child under this parent, or "parent_attr.0" if parent has no children
private String getLastChildAttribute(OracleConnection connection, String catalogue, String parent_attribute) {
String queryLastChild = "SELECT attribute FROM vstd_media_cat_attributes " +
"WHERE catalogue=:1 AND parent_attr=:2 ORDER BY sort_sequence DESC";
String lastChildAttribute;
PreparedStatement ps;
try {
ps = connection.prepareStatement(queryLastChild);
ps.setString(1, catalogue);
ps.setString(2, parent_attribute);
ResultSet rs = ps.executeQuery();
/* If a result is returned, the selected parent already has children.
* If not set the lastChildAttribute to parent_attr.0
if (rs.next()) {
lastChildAttribute = rs.getString("attribute");
} else {
lastChildAttribute = parent_attribute.concat(".0");
rs.close();
return lastChildAttribute;
} catch (SQLException e) {
e.printStackTrace();
return null;
* This helper method determines the position of the last node in the attribute.
* i.e for 3.5.2 it returns 2, for 2.1 it returns 1 etc.
* @param attribute
* @return position of last node in this attribute
private int getLastNodePosition(String attribute) {
StringTokenizer tokenizer = new StringTokenizer(attribute, ".");
String lastNodePosition = "0";
while( tokenizer.hasMoreTokens() ) {
lastNodePosition = tokenizer.nextToken();
return Integer.parseInt(lastNodePosition);
* This method calculates the attribute of a node being inserted
* by incrementing the last child position by 1 and attaching the
* incremented position to the parent.
* @param parent_attr
* @param lastPosition
* @return attribute of the new node
private String createNewNodeAttribute(String parent_attr, int lastPosition) {
String newPosition = new Integer(lastPosition + 1).toString();
return parent_attr.concat("." + newPosition);
* This method checks if the required sequence number for a new node is already in use and
* handles the sequence numbers accordingly.
* If the sequence number for a new node is NOT IN USE, the method doesn't do anything.
* If the sequence number for a new node is IN USE, the method searches for the next free
* sequence number by incrementing the number by one and repeating the query until no result
* is found. Then all the sequence numbers between the required number (including, >= relation)
* and the nearest found free number (not including, < relation) are incremented by 1, as to
* make space for the new node.
* @param connection
* @param catalogue
* @param newNodeSequenceNumber required sequence number for the new node
private void setSequenceNumbers(OracleConnection connection, String catalogue, int newNodeSequenceNumber) {
// 1. check if the new sequence number exists - if no do nothing
// if yes - increment by one and see if exists
// repeat until free sequence number exists
// when found increment all sequence numbers freeSeqNr > seqNr >= newSeqNr
String query = "SELECT sort_sequence FROM vstd_media_cat_attributes " +
"WHERE catalogue=:1 AND sort_sequence=:2";
PreparedStatement ps;
try {
ps = connection.prepareStatement(query);
ps.setString(1, catalogue);
ps.setInt(2, newNodeSequenceNumber);
ResultSet rs = ps.executeQuery();
// if no result, the required sequence number is free - nothing to do
if( rs.next() ) {
int freeSequenceNumber = newNodeSequenceNumber;
do {
ps.setString(1, catalogue);
ps.setInt(2, freeSequenceNumber++);
rs = ps.executeQuery();
} while( rs.next() );
// increment sequence numbers - call stored procedure
String callUpdateSeqeunceNrs = "{ call fasi_lob.pack_gliederung.updateSeqNumbers(:1, :2, :3) }";
CallableStatement cst = connection.prepareCall(callUpdateSeqeunceNrs);
cst.setString(1, catalogue);
cst.setInt(2, newNodeSequenceNumber);
cst.setInt(3, freeSequenceNumber);
cst.execute();
cst.close();
// String query2 = "UPDATE vstd_media_cat_attributes " +
// "SET sort_sequence = (sort_sequence + 1 ) " +
// "WHERE catalogue=:1 sort_sequnce >=:2 AND sort_sequence <:3";
// PreparedStatement ps2;
// ps2 = connection.prepareStatement(query2);
// ps2.setString(1, catalogue);
// ps2.setInt(2, newNodeSequenceNumber);
// ps2.setInt(3, freeSequenceNumber);
// ps.executeUpdate();
// ps.close();
} // end of if block
rs.close();
} catch (SQLException e) {
e.printStackTrace();
* This method finds the last sequence number preceding the sequence number of a node
* that is going to be inserted. The preceding sequence number is required to calculate
* the sequence number of the new node.
* We perform a hierarchical query starting from the parent node: if a result is returned,
* we assign the parent's farthest descendant's node sequence number; if no result
* is returned, we assign the parent's sequence number.
* @param connection
* @param catalogue
* @param parent_attr parent attribute of the new node
* @return
private int getPrecedingSequenceNumber(OracleConnection connection, String catalogue, String parent_attr) {
int sequenceNumber = 0;
String query = "SELECT sort_sequence FROM vstd_media_cat_attributes " +
"WHERE catalogue=:1 " +
"CONNECT BY PRIOR attribute = parent_attr START WITH parent_attr=:2 " +
"ORDER BY sort_sequence DESC";
try {
PreparedStatement ps = connection.prepareStatement(query);
ps.setString(1, catalogue);
ps.setString(2, parent_attr);
ResultSet rs = ps.executeQuery();
if ( rs.next() ) {
sequenceNumber = rs.getInt("sort_sequence");
} else {
// TODO: ggf fetch from request!
sequenceNumber = -1;
rs.close();
ps.close();
} catch (SQLException e) {
e.printStackTrace();
return sequenceNumber;
}After further googling I figured out what was causing the problem: in eclipse I was referring to external libraries located in eclipse/plugins directory, whereas Tomcat was referring to the same libraries (possibly older versions) in it's common/lib directory.
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Problem in connecting to database from webdynpro for java
Hi
I have a problem in connecting to database from webdynpro application
I am using oracle 10 express edition as database and was able to connect to database from a java application.But was unable to connect from a webdynpro for java.
<b>I guess webdynpro for java uses open sql instead of vendor sql(I looked in the visual admin ,DB is using open sql) so unable to connect to database.Am i right.?</b>
Do i need to make any settings in the visual admin to make it work?
How to solve this problem.Please give me pointers
Thanks
BalaHi,
For connecting to Oracle, either you can use the normal JDBC connectivty code directly which is given below :
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@Oracle_server_ip:Oracle port:SID of the Database","user_name","password");
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("your query");
In case you want to fetch data through ejbs, these are the steps to be followed :
1) Open the J2EE perspective
2) Create an EJB Module project
3) Right click on ejbModule, create a new EJB (select your EJB type)
4) While creating the ejb itself, you can add business methods by clicking Next in the UI. Another option is after creating the ejb, write the method in the bean, then select the method from ejb-jar.xml -> <bean name> ->method. Right click and select propogate to local & remote.
5) Double click on ejb-j2ee-engine.xml. select your bean and specify a Jndi name for eg: MyJndi.
6) Right click on the EJB project and add classes12.zip file (provided by Oracle) to its build path. (under libraries tab). Also check the same file under Order & Export.
7) Create an Enterprise Application project.
8) Right click on the EJB module project and select add to EAR project, then select the created EAR project.
9) Right click on the EJB project, select Build EJB Archive
10) Right click on the EAR project, select Build Application Archive
11) Open the WebDynpro perspective, open a new project, right click on the project ->properties. Do the following configurations :-
Java Build path - select the EJB project from projects , check the selected project under Order & Export
Project references select the EAR project
WebDynpro references select sharing references tab, click add & make an entry as : <vendor>/<EAR project name without .ear extension>
You can find the vendor name under application-j2ee-engine.xml file of the EAR project. By default it is sap.com. So if my EAR projects name is ABC, my entry would look like sap.com/ABC
12) Now the configurations are over and the EJB can be invoked by writing the client code inside the webdynpro component. Like:
InitialContext context = new InitialContext();
Object obj = context.lookup("MyJndi");
MyEJBHome home = MyEJBHome)PortableRemoteObject.narrow(obj,MyEJBHome.class);
MyEJB mybean = home.create();
int a = 0;
a= mybean.add(10,15);
wdContext.currentContextElement().setSum(a);
where MyEJB is my EJB name and MyJndi is my JNDI name
To connect to Oracle , you can write the usual Java code (given below) as a business methos of the ejb (similar to add() method in the example). And access it like mybean.<businessMethodName>().
DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@Oracle_server_ip:Oracle port:SID of the Database","user_name","password");
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("your query");
Extracted from Re: Webdynpro and Oracle
http://help.sap.com/saphelp_webas630/helpdata/en/b0/6e62f30cbe9e44977c78dbdc7a6b27/frameset.htm
May be of use to understand the VA Conf /people/varadharajan.krishnasamy/blog/2007/02/27/configuring-jdbc-connector-service-to-perform-database-lookups
Regards
Ayyapparaj -
Can i add a servlet in oracle database for webservices without java and how?
HI
can i add a servlet in oracle database for webservices without java and how?
Please help
ThanksDear Frank,
I have done as follows
created a form with a button, and in my button pressed event I wrote
WEB.SHOW_DOCUMENT('javascript:openMyURL("http://192.168.1.34/HELP/ADMF0005.html");', '_Self');
and in my formsweb.cfg I have the following
HTMLbeforeForm=<script> function OpenMyURL(page){window.open(page,"myURL","width=700,width=400,top=0,left=0,toolbar=no,menubar=no"); } </script>
When I click on the button it is coming with toolbar , etc as well as no page found is coming with the following in the address bar.
javascript:openMyURL("http://192.168.1.34/HELP/ADMF0005.html");
My html view source comes as below for the form
<HEAD><TITLE>Oracle9iAS Forms Services</TITLE></HEAD>
<BODY >
<script> function OpenMyURL(page){window.open(page,"myURL","width=700,width=400,top=0,left=0,toolbar=no,menubar=no"); } </script>
<!-- Forms applet definition (start) -->
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codebase="/forms90/jinitiator/jinit.exe#Version=1,3,1,9"
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I am using Forms [32 Bit] Version 9.0.2.7.0 -
What the Enviroment required for java databases programs?
Hi guys
What the enviroment required for java databases programs?
If I have oracle of version 9i and java 1.4.1 platform
do I need Jdeveloper platform ?What the enviroment required for java databases programs?What do you mean by "environment"?
f I have oracle of version 9i and java 1.4.1 platformYou just need to download Oracle's 9i JDBC driver (ojdbc14.jar) and put that in your CLASSPATH. Then write JDBC code to connect to Oracle and issue SQL commands.
do I need Jdeveloper platform ?No, JDeveloper is an IDE. Not required.
Why Java 1.4.1? We're up to Java 6 now. You're two major versions of the JDK behind.
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Oracle database 11g certification for Java developer
Hello,
I'm Java developer, OCPJP 6 ( Oracle Certified Professional, Java Programmer +6+ ) and
I decided to pass exams: 1Z0-051 and 1Z0-052 to get OCA ( Oracle Database +11g+ Administrator Certified Associate ) certificate,
but I need some advice, maybe i should seek other certificate, that would be more valuable for Java developer, than OCA.
Thanks for advice.The answer of whether a particular certification is valuable depends on you, not the tests themselves. The Oracle Certified Master for example is an extremely prestigious certification, and I have considered seeking it at some point in the future to improve my professional credentials. However, the same certification would have absolutely no value to my wife, because she's a homemaker with no interest or intent of ever working with Oracle.
Using an example a little closer to yours, only reversed --- I work as a DBA and PL/SQL developer. On several occasions I have dabbled with Java, and took a couple of classes when I worked for Oracle. I could code in Java if I had to, but wouldn't really be good without a lot of practice. However, I've never really had a sufficient need in my work to dig in and really practice enough to use it. I considered going for the Oracle Java certifications as a means of kick-starting that and getting to the point where it was really a viable option in my development. Ultimately I decided not to because I've been working with Oracle for better than fifteen years and there has never been an occasion where I really felt a need to know Java. If I were to spend a bunch of time improving my Java skills just for the certification, there's no guarantee I would ever use them after that.
Coming back to you -- if you already need SQL and DBA skills in your work, then those certifications should be of value to you immediately. If you think that you might work (or want to work) more with SQL and DBA-level skills in the future, then they should be of value to you in the future. If you won't use the skills now or ever, then the exams do nothing but add a line to your resume (which still has value, but you must determine how much).
Edited by: matthew_morris on Apr 30, 2012 1:56 PM -
Persistenance for Java Objects Using Toplink
Hi All Happy New Year
I am trying the a tutorial in Jdeveloper 10.1.3.0.4 called
Provide Persistenance for Java Objects Using Toplink.
I have followed the instructions and get the following error.
com.evermind.reflect.UndeclaredExceptionTypeException: oracle.oc4j.rmi.OracleRemoteException
at __Proxy1.persistEntity(Unknown Source)
at acme.ejb.session.EmpSessionClient.main(EmpSessionClient.java:29)
oracle.oc4j.rmi.OracleRemoteException: Invocation error: java.lang.NoSuchMethodException: acme.ejb.session.EmpSession.persistEntity(java.lang.Object)
The release notes mention TopLink POJO's Must Implement java.io.Serializable When Returned From a Session Bean's Remote Interface (4902787) When creating a session bean facade for TopLink POJO objects, you must implement java.io.Serializable for each of the TopLink POJO objects returned from the SessionBean facade through a remote interface. This is typically required when using ADF Swing, a EJB Sample Client, or when your EJB Session Bean resides on a separate application server from the client. You can also tell you you need to implement java.io.Serializable when you get the following exception:
com.evermind.reflect.UndeclaredExceptionTypeException:
/oracle.oc4j.rmi.OracleRemoteException/
at __Proxy1.[Your Class Name Here] (Unknown Source)
The workaround is to manually edit each POJO object to implement java.io.Serializable.
I have only one POJO which is declared as follows:
public class EmpInfo implements Serializable {
Can anybody help me understand what I need to do to get it to work?
Many Thanks in AdvanceHi,
can you send me your test scenario/project at anuj dot k dot jain at oracle dot com. I tried reproducing this but was unable to do so.
Thanks,
anuj dot k dot jain at oracle dot com -
Looking for answer keys for "Object First with Java"
Where can I find a book with anwser keys for the book " Object First with Java" Third Edition?
zxcvbnm wrote:
Where can I find a book with anwser keys for the book " Object First with Java" Third Edition?This ought to be an interesting thread. :) -
Setting System DSN for MS Access Database using Java Code
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Replies are deeply appreciated...I found a 3rd Party MS Access JDBC Driver from a Google search. I downloaded and tried the free trial version. It worked fine but we opted not to purchase the full version and went a different route. If you don't find it, let me know and I'll see if I can track down the name of the product we tested.
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