A) General
1. Differences between Applications and Applets
2. Simple Java example with Life cycle with HTML file
3. Drawing Strings & Graphics on Applet window
4. Reading HTML <param> Tag in Applet Example
5. Drawing Images & Playing Audio Clips
B) Special
6. HTML to Applet & Inter-Applet Communication
7. Banner, Applet cum Application
8. Converting Applet to Application
9. Converting Application to Applet
10. Applet with AWT GUI – Buttons
11. Difference between start and init in Applet
Hi,
How can i send array of string objects from an applet to a servlet and how can i see it in the servlet?
Here is your posted code.
so please help me to send array of object using ur code only.
OutputStream ostream = ucon.getOutputStream( );
ObjectOutputStream oos = new ObjectOutputStream(ostream);
Integer i1 = new Integer( str );
oos.writeObject( i1 ); —> here how can i send the more than 2 objects
Thanks & Regards
Bikash
Hi;
In previous post i have mention wrong sql query i.e instead of
” select count(*) from table A where empno=?; (?=empno of A) ”
the query is
” select count(*) from table B where empno=?; (?=empno of A)”
Hi,
In jdbc i have a requirement i.e
1. I have to access the empno from table A.
2. with empno from A i have to check the total no of same empno present in another table i.e B.
i.e select count(*) from table A where empno=?; (?=empno of A)
3. If count(*) >0 then i don’t want to insert the corresponding record into table B.
4. if count(*) =0 then i want to insert the record in table B.
The fact is i have implemented the same in my code .When i execute my code it is very slow.
For this i am using simple JDBC. I can’t use Hibernate.
How can i speed up my code performance.
Sorry i can’t attach my code due to some problem.
Please help me on this.
Thanks & Regards
Bikash
If you cannot use Hibernate, use connection pooling supported by your tool like Tomcat or Weblogic etc.
Hi ,
Actually it’s a simple java application. I am not using any servlet .so how can it possible ?
Thanks & Regards
Bikash
Hi,
Could u clarifying me what is the difference between java 1.6 and 1.7 ?
i.e what are the enhancement in java 1.7 ?
with regards
Bikash
See these links in way2java:
http://way2java.com/java-versions-2/jdk-1-6-java-se-6-jdk-1-7-versions/
http://way2java.com/java-versions-2/jdk-1-7-features/
http://way2java.com/java-versions-2/latest-java-7-jdk-1-7-new-features-added/
http://way2java.com/java-versions-2/new-switch-with-string-support-java-7-features/
http://way2java.com/java-versions-2/try-with-resources-example-in-java-7/
JDK 1.8
http://way2java.com/java-versions-2/jdk-1-8-features/
http://way2java.com/java-versions-2/java-lambda-function/
Hi ,
can u tell me What is the difference between Filter and Servlet with a small example ?
with regards
Bikash
I put shortly in the site.
Hi,
I am new to testing domain.
Can u tell me what is unit testing and why we require that ?
With regards
Bikash
I am not aware of.
HI Sir,
I have a tool which will read data from the main table and inserted same data into mytable. The main table has 2 lakhs of records.
I am using preparedstatement to read and insert the data.
But the problem is that it has taken lot of time to read and insert.
How can i speed up my tool perfermance?
Can i use addBatch()? if yes i want to read and insert 10,000 records at a time and then i will use con.commit.
So that when next time i start my tool it will not read and insert the old records.i.e first 10000 records.It will start from new one i.e from 10001.
How can i do this ?
If no , please guide me what can i do to increase my tool perfermance ?
I am using simple jdbc.
with regards
Bikash
Use Hibernate. Hibernate has maximum optimizations.
Hi,
I have a properties file which contains db credentials. I have to access the file dynamically in my java file. i.e i don’t want to hard code the path of the file .
How can i access the file and how can i read all the values from that file in my java application.
Please help me.
with regards
Bikash
Use File class “pathSeprator” and “separatorChar”.
Hi Sir,
I have devloped a tool, in that i have an requirement to popup a message to the user.
For an example
In that tool some i have implemented a query that deletes some records from the table.
So i have to show the user how many recors has deleted from the db through a pop message.
My tool is a simple java file.
So how can i implement this.
with regards
Bikash
Use Swing Message box.
Hi sir,
I have to insert more than 1000 of record in mytable.For that i have developed a tool which will insert records from mastertable to my table. But when i run my tool , my tool can inserted only 148 records for 1st run and it will showing a error i.e
java.sql.SQLException: ORA-00604: error occurred at recursive SQL level 1
ORA-01000: maximum open cursors exceeded
ORA-00604: error occurred at recursive SQL level 1
ORA-01000: maximum open cursors exceeded
ORA-01000: maximum open cursors exceeded
at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70)
at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:112)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:173)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:455)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:413)
at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:1030)
at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:194)
at oracle.jdbc.driver.T4CPreparedStatement.executeForDescribe(T4CPreparedStatement.java:785)
at oracle.jdbc.driver.T4CPreparedStatement.executeMaybeDescribe(T4CPreparedStatement.java:860)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1186)
at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3381)
at oracle.jdbc.driver.OraclePreparedStatement.executeQuery(OraclePreparedStatement.java:3425)
at oracle.jdbc.driver.OraclePreparedStatementWrapper.executeQuery(OraclePreparedStatementWrapper.java:1490)
at com.per.sub.ReadNostroReadCount.main
After that it will insert 148/2=74 records into the table with same above specified error.
After that it will insert 74/2=37 records into the table with same above specified error.
and will insert records so on with same error.
But at last it will enter only single record with same error and after that it will not enter any reocord.
I am afraid why it happens like that.
Please help me and please solve the problem.
with regards
Bikash
Hi sir,
i have 2 tables.One is mastertable and another is mytable and both have their own primary key .There is no foreign key relationship between these 2 tables.
Now have a tool in which i have 2 stmts.i.e
a. delete the records from mytble whose balance is 0.
b. insert the new reocords into mytable from mastertable whose balance is not 0.
My requirement is :-
Before inserting the records into mytable i have to check the primary key value of mastertable is present in mytable or not.
if it is present then i will not insert the record into mytable
If it is not present then i will enter the records into mytable.
I am doing with this code
……………
…………..
……………
st=con.createStatement();
ResultSet rs1=st.executeQuery(“select statement_tag61 from NOSTRO_KASTLE”);
while(rs1.next())
{
stmttag=rs1.getString(1);
System.out.println(“nostro is”+stmttag);
count++;
//***************** start count(*)
try
{
ps=con.prepareStatement(nostro_pk_no);
ps.setString(1, stmttag);
System.out.println(“the value of str is”+stmttag);
rs=ps.executeQuery();—-> here i am getting error
while(rs.next())
{
no=rs.getInt(1);
}
if(no==0)
{
System.out.println(“new nostro”);
}
else
{
System.out.println(“old record”);
}
System.out.println(“resultset is created”);
//ps.close();
//con.close();
}
catch(Exception e)
{
System.out.println(“Got an exception”);
e.printStackTrace();
}
//*************** end conunt(*)
}
rs1.close();
//System.out.println(“total records are”+count);
}
catch(Exception e)
{
e.printStackTrace();
}
*** i hv mention a piece of code.
i am not getting my output with the above implemented logic.
So how can i do it, Please tell me.
with regards
BIkash
Hi ,
I am developing a tool which will do 3 things.
A. delete some records based on some condition.
B. select records from one table.
C. Insert into another table.
I have already imlemented it. First time it has worked.But when i run it from 2nd time onwards , i have to commit my db explicitely.
So i have used con.commit(); in my programme. But it is still not working since i run commit command in db explicitely.
So what can i do to solve the issue ?
Please tell me.
with regards
Bikash
Just call con.commit(), where con is an object of Connection interface, in your code after insertion and deletion of records. Your problem will be solved.
Hi ,
Thanks for your suggestion.
But i have call con.commit() after each executeUpdate() method .but it won’t work.
Could u clarify me how many times we have to call con.commit() in our programme?
I have called this method for each transaction.
Is it fine or i have to call one and only one time in the programme.
Thanks & Regards
Bikash
If you insert and delete in the same code, call after insert and also after delete. If you have separate programs, call only once at the end of code.
Hi sir,
How can i check web.xml is working fine or not in eclipse ide?
with regards
Bikash
Your output will tell you. Weblogic clearly tells where the corruption occurred.
Hi sir,
I have an account table as like this
Accno Accnm accbal
1 Kumar 0
2 sanu 2
I have to delete the record whose accbal=0 .
My code is:-
package com.per.sub;
import java.sql.*;
class Check {
static void main(String[] args)
{
int n=0;
int i=0;
Connection con=null;
PreparedStatement ps=null;
String del_query=”delete from accounts where accbal=?”;
try
{
Class.forName(“oracle.jdbc.driver.OracleDriver”);
=DriverManager.getConnection(“jdbc:oracle:thin:@localhost:1521:orcl”,”scott”,”tiger”);
System.out.println(“connected successfully”);
ps=con.prepareStatement(del_query);
ps.setInt(1, i);
n=ps.executeUpdate();
System.out.println(n+”records are deleted”);
}
catch(Exception e)
{
e.printStackTrace();
}
finally
{
try{
if (ps != null) {
ps.close();
}
if (con!= null) {
con.close();
}
}
catch(Exception e1)
{
e1.printStackTrace();
}
}
}
}
But the record is not deleted.But if i delete the record where accbal=2 then it works.
Please tell me what is the problem?
with regards
bikash
Your program is okay. Try like this: ps.setInt(1, 0);
Put 0 instead of i directly.
Hi Sir,
How can i read db credential from web.xml ?
with regards
Bikash
Hi Sir,
I have an requirement to write 2 update statement in my java file and the 2 files will be fired one after another.i.e 1st update stmt and then the 2nd stmt . These 2 update stmt are different i.e 1st stmt update one record and 2nd one update the other column.
How can i do it ?
Can do it by addBatch() ? If yes then how ? If not , what is the another way to achive ?
Please help me ?
with regards
Bikash
Simply call two times stmt one after another. If required, in the middle of two stmt objects give con.commit(). addBatch() also works.
Hi Sir,
Is there any function named instr(). if it is then what is the use of this and how can we use it?
Please tell me ?
with regards
Bikash
I am not aware of.
Hi Sir,
how can i conver the string value to long.i.e
String inward=”30.98″;
I have to convert inward to long type.
If i use long l1=Long.parseLong(inward);
I found Exception in thread “main” java.lang.NumberFormatException: For input string: “30.98”.
How can i do it ?
Pls help me
with regards
bikash
Naturally, how you convert a floating-point value into a long. First parse to double. Then cast to long.
Hi Sir,
I have a string i.e
String str=” id=1,nm=p,age=32″;
How can i print nm value from str .
Please help me.
with regards
Bikash
Find the index of nm, From nm, have a substring.
Hi Sir,
I have an simple object which contains some data.
I have to print all the data that object contains.
How can i do this ?
Please help me.
with regards
Bikash
Override toString() method as follows.
public class Employee
{
int salary;
String name;
public String toString()
{
return “Employee Name: ” + name + ” and Employee Salary Rs.” + salary;
}
public static void main(String args[])
{
Employee emp1 = new Employee(); //
Employee emp2 = new Employee();
emp1.salary = 5000;
emp2.salary = 6000;
emp1.name =”biksah”;
emp2.name =”Rao”;
System.out.println(emp1);
System.out.println(emp2);
}
}
Hi sir,
I have a textfield in my applet and i.e
private TextField nostroValueDate;
nostroValueDate = new TextField( 10 );
nostroValueDate.addKeyListener(this);
Requirement :-
—————–
1. I have to polulate the date in nostroValueDate field which is coming from the database.
2. But the date is coming and it has shown for fraction of time in the nostroValueDate filed and after that is get disable.
3. I have to fix the data shown in the textfield.
How can i do this ?
Please help me
Thanks & Regards
Bikash
Writing code is difficult to me as I am very busy with my regular activities. way2java is my hobby but not profession.
Hi,
I have an applet which have some drop dwon fields and text fields and one button which are interlinked to each other.i.e when i select one value from one field then another field will polulated. i.e the data came from the database and populated in the corresponding field.
Requiremnt:-
When i select a value from the drop down list then the button field will blinking . I have to stop the blinking.
How can i do it ?
Please help me.
One way is for button label keep in sleep() method.
Hi sir,
I am not getting ur respnse regarding button blinking.
1.Which logic that i have to place in sleep() method ?
2.Where i have to place the sleep method ?
Can u please send me the demo code ?
Thanks & Regards
Bikash
in sleep() method, validiate and invalidate the button. Take the help of your friends.
Hi,
I have 2 files having some records/contents. My requirement is that i have to find out the common records as well as non matching records.
How can i get the answer ?
Please help me.
Read them into java DS and use:
Existence of Common Elements with disjoint(): http://way2java.com/collections/existence-of-common-elements-with-disjoint/
Hi,
I am new to stored procedure. I have one table and i have written a stored procedure.
My doubt is how to execute the below stored procedure.
Please help me as soon as possible.
oracle table structure
——————————-
CREATE TABLE ACCOUNTS
( ACCNO NUMBER(10),
ACCNM VARCHAR2(10 BYTE),
ACCBAL NUMBER(7,4)
)
Procedure
—————
CREATE OR REPLACE PROCEDURE addinterest(
ano IN accounts.accno%TYPE,
bal OUT accounts.accbal%TYPE)
IS
BEGIN
select accbal into bal from accounts where accno=ano;
bal:=bal+bal*0.5;
update accounts set accbal=bal where accno=ano;
end;
Please help me how to execute the stored procedure in oracle.
Just type the procedure at SQL prompt and type enter key.
Hi,
I am new to stored procedure. I have one table and i have written a stored procedure.
My doubt is how to execute the below stored procedure.
Please help me as soon as possible.
oracle table structure
——————————-
CREATE TABLE ACCOUNTS
( ACCNO NUMBER(10),
ACCNM VARCHAR2(10 BYTE),
ACCBAL NUMBER(7,4)
)
Procedure
—————
CREATE OR REPLACE PROCEDURE addinterest(
ano IN accounts.accno%TYPE,
bal OUT accounts.accbal%TYPE)
IS
BEGIN
select accbal into bal from accounts where accno=ano;
bal:=bal+bal*0.5;
update accounts set accbal=bal where accno=ano;
end;
Please help me how to execute the stored procedure in oracle.
– See more at: http://way2java.com/view-all/view-all-applets/comment-page-1/#comment-95504
HI Sir,
I hv create a sp which contains one select stmt and one update stmt in oracle and i have to access it through my java class .But i am getting some errors .
I mention here my .java file,procedure and table structure and the error file.
Please make some necessary correction and send me updated code.
Please respond this post as soon as possible.
The details are as follows:-
StoredProcedure.java
——————————–
import java.sql.*;
class StoredProcedure
{
public static void main(String[] args)throws Exception
{
try
{
Class.forName(“oracle.jdbc.driver.OracleDriver”);
Connection con = DriverManager.getConnection(“jdbc:oracle:thin:@localhost:orcl”,”scott”,”tiger”);
CallableStatement cst = con.prepareCall(“{call addinterest(?,?)}”);
cst.registerOutParameter(2,Types.FLOAT);
cst.setInt(1,123);
cst.execute();
float accbal = cst.getFloat(2);
System.out.println(“Modified balance is rs:” +accbal);
cst.close();
con.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
oracle table structure
——————————-
CREATE TABLE ACCOUNTS
( ACCNO NUMBER(10),
ACCNM VARCHAR2(10 BYTE),
ACCBAL NUMBER(7,4)
)
Procedure
—————
CREATE OR REPLACE PROCEDURE addinterest(
ano IN accounts.accno%TYPE,
bal OUT accounts.accbal%TYPE)
IS
BEGIN
select accbal into bal from accounts where accno=ano;
bal:=bal+bal*0.5;
update accounts set accbal=bal where accno=ano;
end;
and the error is
———————
java.sql.SQLException: ORA-01403: no data found
ORA-06512: at “RETDEV.ADDINTEREST”, line 8
ORA-06512: at line 1
at oracle.jdbc.driver.SQLStateMapping.newSQLException(SQLStateMapping.java:70)
at oracle.jdbc.driver.DatabaseError.newSQLException(DatabaseError.java:112)
at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:173)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:455)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:413)
at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:1030)
at oracle.jdbc.driver.T4CCallableStatement.doOall8(T4CCallableStatement.java:191)
at oracle.jdbc.driver.T4CCallableStatement.executeForRows(T4CCallableStatement.java:944)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1222)
at oracle.jdbc.driver.OraclePreparedStatement.executeInternal(OraclePreparedStatement.java:3381)
at oracle.jdbc.driver.OraclePreparedStatement.execute(OraclePreparedStatement.java:3482)
at oracle.jdbc.driver.OracleCallableStatement.execute(OracleCallableStatement.java:3856)
at oracle.jdbc.driver.OraclePreparedStatementWrapper.execute(OraclePreparedStatementWrapper.java:1373)
at com.per.sub.StoredProcedure.main(StoredProcedure.java:20)
Check once procedure code.
Your procedure code is not matching with call of two question marks.
Hi,
I am new to stored procedure. I have one table and i have written a stored procedure.
My doubt is how to execute the below stored procedure.
Please help me as soon as possible.
oracle table structure
——————————-
CREATE TABLE ACCOUNTS
( ACCNO NUMBER(10),
ACCNM VARCHAR2(10 BYTE),
ACCBAL NUMBER(7,4)
)
Procedure
—————
CREATE OR REPLACE PROCEDURE addinterest(
ano IN accounts.accno%TYPE,
bal OUT accounts.accbal%TYPE)
IS
BEGIN
select accbal into bal from accounts where accno=ano;
bal:=bal+bal*0.5;
update accounts set accbal=bal where accno=ano;
end;
Please help me how to execute the stored procedure in oracle.
Hi sir,
Thank for ur response.
I have gone through the code as u have mentioned above .But i didn’t get my result.
The contrl can’t enter into the while loop that i have placed in my programme.I am posting my programme .Please go through this.
import java.sql.*;
class Populate
{
public static void main(String[] args)
{
try
{
Class.forName(“oracle.jdbc.driver.OracleDriver”);
String cs=”jdbc:oracle:thin:@localhost:1521:orcl”;
Connection con=DriverManager.getConnection(cs,”SCOTT”,”TIGER”);
Statement st=con.createStatement();
ResultSet rs=st.executeQuery(“select sid,sname from student where amt <0");
System.out.println("rsultset object created");
while(rs.next())
{
//float a =rs.getFloat(1);
int sid=rs.getInt(1);
String nm=rs.getString(2);
System.out.println("a/c details");
System.out.println("a/c no is :" + sid);
System.out.println("name is "+nm);
}
System.out.println("at line no 25");
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
The output of the above programme is
rsultset object created
at line no 25
But i have more than 100 records in my table and i want to populate all the records in the dropdown list of my jsp.
How can i do it?
Please help me as soon as possible.
with regards
Bikash
I get you on Sunday. I am busy right now.
Hi sir,
my requirement is as follows:-
1.In my database has amount column having datatype number(12,4).That column contains both + and – values.
2. I have to fetch only – records from the database.
3. Those data has to transfer to the web layer i.e jsp and polulate all the negetive values in one drop down list in jsp.
How can i do it ?
Please help me with code .
with regards
Bikash
Write a query where amount < 0 which gives negative values. Write res.next() in a loop and populate drop down list.
Hi sir,
In my ResultSet object i have 200 records . I want to see those records .How can i see ?
The code should be generic i.e industry standard.
Please reply this post as soon as possible.
with regards
Bikash
Until and unless you print somewhere, you cannot see.
Hi sir,
I have my code below.I can get the values from the table but the same records could’t inserted in another table.
The code is
//package com.per.sub;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.sql.*;
public class SelectInsert
{
public static void main(String[] argv) throws Exception
{
try
{
Connection con = DriverManager.getConnection( “jdbc:oracle:thin:@localhost:1521:orcl”,”soctt”,”tiger”);
Connection con1 = DriverManager.getConnection( “jdbc:oracle:thin:@localhost:1521:orcl”,”soctt”,”tiger”);
//String sql = “INSERT INTO employee1(“+ “empid,”+ “empname)”+ “VALUES(?,?)”;
String sql = “INSERT INTO employee1(empid,empname)”+ “VALUES(?,?)”;
//Statement statement = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE);
Statement statement = con.createStatement();
PreparedStatement pstmt = con1.prepareStatement(sql);
ResultSet rs = statement.executeQuery(“SELECT * FROM employee”);
while ( rs.next() )
{
/*String nm = rs.getString(2);
Boolean ac = rs.getBoolean(3);
String log = rs.getString(4);
String pass = rs.getString(5);
pstmt.setString(1, nm);
pstmt.setBoolean(2, ac);
pstmt.setString(3, log);
pstmt.setString(4, pass);
pstmt.executeUpdate();*/
int id=rs.getInt(1);
String nm=rs.getString(2);
pstmt.setInt(1, id);
pstmt.setString(2, nm);
}
con.close();statement.close();
con1.close();pstmt.close();rs.close();
}
catch (SQLException e)
{
System.out.println(“could not get JDBC connection: ” +e);
}
}
}
Please make necessary correction and update me with the correct code.
with regards
Bikash
Hi sir,
I have my code below.I can get the values from the table but the same records could’t inserted in another table.
Please make necessary correction and update me with the correct code.
with regards
Bikash
Hi Sir,
I have an requirement to get the records from one table and i have to insert the same records in another table.
And it can be done in one java class.
How it is possible >
Can u provide the code ?
with regards
Bikash
– See more at: http://way2java.com/view-all/view-all-jdbc/comment-page-1/#comment-93085
Retrieve in ResultSet object. In iteration with next(), write update command to insert.
Hello Sir,
I have an requirement to fetch date in this format i.e 11/07/2014 (dd/mm/yyyy) from the database .
What would be the code to get the date as per my requirement.Please help me.
If i used the getDate() method i can get the date like 2014-07-11.
with regards
bikash
Use SimpleDateFormat or DateFormat class.
Hi sir,
Would you tell me why i am getting this error ?
I have seen in tomcat’s log i.e catalina.out.The error msg is as follows
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at org.apache.catalina.valves.RequestFilterValve.process(RequestFilterValve.java:276)
at org.apache.catalina.valves.RemoteAddrValve.invoke(RemoteAddrValve.java:81)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:174)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:875)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Thread.java:595)
Please reply this post as soon as possible.
with regards
Bikash
Hi Sir,
I have an applet and servlet communication using tomcat.I have an System.out.prinln in my servlet. Where i can find out the output i.e which tomcat file i can find out the restult.
Please help me.
with regards
Bikask
Check at console or put it in paint() method of applet.
Thanks for ur reply.
Actually the two .html files are not visible .Would u provide these 2 html files once again.
with regards
bikash
Hi Sir,
I have sent some post since yesterdat.But i am not getting any response from ur side.
Whatever code that u have given with that myapplet can’t connect to servlet.I am getting following exception
some problemjava.io.IOException: Server returned HTTP response code: 502 for URL: https://ip/webapps/folder_name/CustomServlet
I have tried with weblogic server. Check yourself.
Hello Sir,
Thank for the response.In this post the 2 .html files are not visible in any browser i.e (IE,Fire Fox,Google Chrome ). Do me a favour please attach these 2 .html file in this post or mail me on [email protected].
It’s urgent.
Thanks & Regards
Bikash
HTML file nothing but containing
Hello sir,
How can a value can be sent to the servlet for database manipulation after selecting the value from the drop down list of an applet?
a. First of all i need the applet-servlet communication.
b. Then i need the code to send data from applet to servlet?
Please help me soon.
Thanks & regards.
Follow this and may be helpful in your code.
Applet to Servlet Communication
Applet to Servlet communication is of 2 types:
1. Text-based communication
2. Object-based communication
1) Text based Communication
It is assumed that there exists a table Employee with following fields:
empid number
empname varchar2(15)
empsal number(6, 2)
The source code involves 3 programs:
1. FetchRecordApplet.hmtl for calling applet
2. FetchRecordApplet.java to display an UI to take user’s input of empid and forward it to the servlet. This UI receives the employee particulars from the servlet and displays them in the text fields.
3. FetchRecordServlet.java to receive data from the applet, search for database Employee table, take the values and send them to the applet.
When you run this program, you may get Security Exception. To overcome this, do the following:
Browser menu bar Tools Internet Options Security Internet Custom Level Miscellaneous Access Data Sources across domains Select enable
Also with
Browser menu bar Tools Internet Options Security Local Intranet Custom Level Miscellaneous Access Data Sources across domains Select enable
1st Program: FetchRecordApplet.html (copy to examplesWebApp)
2nd Program: FetchRecordApplet.java (copy to examplesWebApp)
(for applet file, web.xml file need not be written)
import java.applet.*; import java.awt.*; import java.awt.event.*;
import java.net.*; import java.io.*;
public class FetchRecordApplet extends Applet implements ActionListener
{
TextField idField, nameField, salaryField ;
Button fetchButton ;
public void init( )
{
setLayout(new BorderLayout( ) );
Panel p1 = new Panel( );
p1.setLayout(new GridLayout( 2, 2, 5, 5 ) );
p1.setBackground(Color.cyan);
Panel p2 = new Panel( );
p2.setBackground(Color.pink);
p2.setLayout(new GridLayout( 2, 2, 5, 5 ));
p1.add( new Label(“Enter Employee ID” ));
p1.add( idField = new TextField(15) );
p1.add( new Label(“Click for Details” ));
p1.add( fetchButton = new Button(“Fetch Details” ));
fetchButton.setBackground(Color.yellow);
p2.add( new Label( “Employee Name” ));
p2.add( nameField = new TextField(15));
p2.add( new Label( “Employee Salary” ));
p2.add( salaryField = new TextField(15) );
fetchButton.addActionListener(this);
add(p1, “North”); add(p2, “South”);
}
public void actionPerformed(ActionEvent e)
{
try
{
String str = idField.getText( );
URL u1 = new URL(“http://home:7001/examplesWebApp/
myFetchRecordServlet?t1=”+str);
URLConnection ucon = u1.openConnection( );
InputStream istream = ucon.getInputStream( );
BufferedReader br = new BufferedReader(new
InputStreamReader(istream));
String details[ ] = new String[2];
int i = 0 ;
String str1=””;
while( (str1 = br.readLine( ) ) != null )
{
details[i] = str1 ;
i + + ;
}
br.close( );
nameField.setText(details[0]);
salaryField.setText(details[1]);
}
catch(Exception e1)
{
nameField.setText(“Some Problem” + e1);
salaryField.setText(“Data not received”);
}
}
}
3rd Program: FetchRecordServlet.java (copy to examplesWebApp)
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.sql.*;
public class FetchRecordServlet extends HttpServlet
{
public void doGet(HttpServletRequest req, HttpServletResponse res) throws
ServletException, IOException
{
res.setContentType(“text/plain”);
PrintWriter out = res.getWriter( );
String idno = req.getParameter(“t1”);
try
{
Class.forName( “sun.jdbc.odbc.JdbcOdbcDriver” );
Connection con = DriverManager.getConnection(
“jdbc:odbc:snrao”,”scott”,”tiger”);
Statement stmt = con.createStatement( );
ResultSet res1 = stmt.executeQuery(“select *from Employee where
empid=” + idno);
res1.next( );
String name = res1.getString(2);
String salary = res1.getString(3);
out.println(name);
out.println(salary);
out.flush( );
res1.close( ); stmt.close( ); con.close( ); out.close( );
}
catch(ClassNotFoundException e)
{
out.println(“The database driver is not found”);
}
catch(SQLException e)
{
out.println(“Name not found”);
out.println(“Salary not found”);
}
}
}
2. Object-based Communication:
In this objects are passed and retrieved.
The source code involves 3 independent programs.
1st Program: ObjectCommunicationApplet.html
2nd Program: ObjectCommunicationApplet.java ( copy it to the examplesWebApp
directory)
import java.applet.*; import java.awt.*; import java.awt.event.*;
import java.net.*; import java.io.*; import java.util.*;
public class ObjectCommunicationApplet extends Applet implements ActionListener
{
TextField idField, nameField, salaryField ;
Button fetchButton;
public void init( )
{
setLayout(new BorderLayout( ) );
Panel p1 = new Panel( );
p1.setLayout(new GridLayout( 2, 2, 5, 5 ));
p1.setBackground(Color.cyan);
Panel p2 = new Panel( );
p2.setBackground(Color.pink);
p2.setLayout(new GridLayout(2,2,5,5));
p1.add( new Label(“Enter Employee ID” ));
p1.add( idField = new TextField(15) );
p1.add( new Label(“Click for Details” ));
p1.add( fetchButton = new Button(“Fetch Details” ));
fetchButton.setBackground(Color.yellow);
p2.add( new Label( “Employee Name” ));
p2.add( nameField = new TextField(15));
p2.add( new Label( “Employee Salary” ));
p2.add( salaryField = new TextField(15) );
fetchButton.addActionListener(this);
add(p1, “North”); add(p2, “South”);
}
public void actionPerformed(ActionEvent e)
{
try
{
String str = idField.getText( );
URL u1 = new URL(“http://home:7001/examplesWebApp/
myObjectCommunicationServlet”);
URLConnection ucon = u1.openConnection( );
ucon.setUseCaches(false);
ucon.setDoInput(true);
ucon.setDoOutput(true);
ucon.setRequestProperty(“Content-Type”, “application/octet-stream”);
// code to send data(employee id) to the servlet
OutputStream ostream = ucon.getOutputStream( );
ObjectOutputStream oos = new ObjectOutputStream(ostream);
Integer i1 = new Integer( str );
oos.writeObject( i1 );
oos.flush( );
oos.close( );
// code to receive data(employee name and salary) from the servlet
InputStream istream = ucon.getInputStream( );
ObjectInputStream ois = new ObjectInputStream(istream);
// get an object from the servlet that contains the data
Object obj = ois.readObject( );
Vector vect1 = (Vector) obj;
ois.close( );
String name = (String) vect1.elementAt( 0 );
String salary = (String) vect1.elementAt( 1 );
nameField.setText(name);
salaryField.setText(salary);
}
catch(Exception e1)
{
nameField.setText(“Some Problem” + e1);
salaryField.setText(“Data not received”);
}
}
}
3rd Program: ObjectCommunicationServlet.java
import javax.servlet.*; import javax.servlet.http.*; import java.io.*;
import java.sql.*; import java.util.*;
public class ObjectCommunicationServlet extends HttpServlet
{
public void service(HttpServletRequest req, HttpServletResponse res) throws
ServletException, IOException
{
res.setContentType(“text/plain”);
ObjectInputStream ois = new ObjectInputStream(req.getInputStream( ));
ObjectOutputStream oos = new ObjectOutputStream(
res.getOutputStream( ) );
res.setContentType(“application/octet-stream”);
try
{
Integer idno1 = (Integer) ois.readObject( );
String idno = idno1.toString( );
Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”);
Connection con = DriverManager.getConnection( “jdbc:odbc:snrao”,
“scott”,”tiger”);
Statement stmt = con.createStatement( );
ResultSet res1 = stmt.executeQuery(“select *from Employee where
empid = ” +idno);
res1.next( );
String name = res1.getString(2);
String salary = res1.getString(3);
Vector vect2 = new Vector( );
vect2.addElement(name);
vect2.addElement(salary);
oos.writeObject(vect2);
res1.close( ); stmt.close( ); con.close( );
}
catch(ClassNotFoundException e)
{
e.printStackTrace( );
}
catch(SQLException e)
{
e.printStackTrace( );
}
}
}
How an applet can communicate servlet using urlconnection?
Help me soon.
Try once on your browser as some browsers keep restrictions.
Sir! I wants to know the methods of passing parameters to applets. Iam nt gettng it here. Can u pls help me……
As all methods are callback methods in Applet, write your own method and call it from any callback method (like init(), start()) etc. with all passing parameters.