Question: How many kinds of enterprise beans does Java has?

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Question: How many kinds of enterprise beans does Java has?

Answer: Java (J2EE) has three kinds of Java beans:

1. Session beans -represent transient conversations with clients. The data will be gone after a session is over

2. Entity beans -represent persistent data and let to store datain a database.

3. Message driven beans - combining features of a session bean and Java Message Service (JMS). They provide possibility to receive asynchronous JMS messages.

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Question: I'm trying to read a file from the jsp file on the server. It works fi

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Question: I'm trying to read a file from the jsp file on the server. It works fine when I try to read the same file on my PC with the following statement:

FileReader f = new FileReader("d: empa.txt");
BufferedReader fi = new BufferedReader(f);

However, when I run the same JSP file with the same statement on the server, I get the exception saying that the file cannot be found...
I am sure that the file file is in the same directory as the JSP file that tries to open it.

FileReader f = new FileReader("a.txt");
BufferedReader fi = new BufferedReader(f);


Here is the error when the above is executed by JSP on the server:

500 Internal Exception
error = java.io.FileNotFoundException: a.txt

Answer: The JSP is not in the same directory as the text file. The JSP is stored in a default location within the server itself because it is compiled to a servlet.
You have two options:
1. Find this location and put your text file there,
or
2. Provide the full path to file reader the full path or give it a relative path (the best choice, since the code will be portable.
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