Databases
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    <pre><code>import java.sql.*; import java.net.*; import java.io.*; import java.util.Enumeration; public class EServer { public static void main(String[] args) { // Net and IO objects ServerSocket ss= null; Socket s = null; BufferedReader bf = null; PrintWriter pw = null; // Queries // Query which retireves all products String allQuery = "Select * from StoreProducts"; // Query which retrieves products which are out of stock String outOfStockQuery = "Select * from StoreProducts where Quantity = 0"; String queryString = ""; String messageBack = ""; // Database objects Connection cn = null; Statement query = null; ResultSet rs = null; String lineRead= ""; ProductCollection pColl = new ProductCollection(); Enumeration pEnumeration; try { // Server socket set up on port 2000 ss = new ServerSocket(2000); System.out.println("...Server socket set up"); // Set up a database Database db = new Database ("darrel", "", "sun.jdbc.odbc.JdbcOdbcDriver", "jdbc:odbc:", "products"); System.out.println("...Database set up"); // Get a connection to the database Database.establishConnection(); cn = Database.getConnection(); System.out.println("...Database connection set up"); //Set up a query object query = cn.createStatement(); // Loop waiting for connections int count = 1; while(true) { System.out.println("...Waiting for connection "+count); count++; s = ss.accept(); pw = new PrintWriter(s.getOutputStream(), true); bf = new BufferedReader(new InputStreamReader(s.getInputStream())); boolean looper = true; while(true) { lineRead = bf.readLine(); switch(lineRead.charAt(0))// { // Out of Stock command case 'O':{ queryString = outOfStockQuery; break; } // All products case 'A':{ queryString = allQuery; break; } // Client has terminated case 'E':{ looper = false; break; } } //Check if client has terminated if(!looper) break; // Client has not terminated // Execute the required query and create result set rs = query.executeQuery(queryString); // Create collection of products pColl = new ProductCollection(); // Process the rows that have been extracted // Place them in pColl Product extractedProduct; while(rs.next()) { *extractedProduct = (Product) pColl.addProduct(rs);* } // Form the collection of products, each terminated by asterisk pEnumeration = pColl.elements(); // messageBack is to be concatenated to so initialise it to the empty string messageBack= ""; while(pEnumeration.hasMoreElements()) { messageBack+=(Product)pEnumeration.nextElement()+"*"; } // Now send back the collection string to the client for display pw.println(messageBack); } } } catch(Exception e) {System.out.println("Trouble setting up the database "+e);} // Close database connection try { cn.close(); } catch(Exception e) {System.out.println("Problem closing connection");} } } </code></pre>
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    1. This table or related slice is empty.
    1. POcreate object object in java confusion
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    1. USAdrian Carneiro
    1. USMilas
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. COhere is the Eserver code im struggling to fetch information and populate in an object can someone help me please as im new in programming thank you
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      1. USMilas
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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