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		Adding Database Items
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		Adding Database Items
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            <h2 class="title" style="clear: both"><a id="addingdatabaseitems"></a>
		Adding Database Items
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      <p>
    Adding (as well as updating, removing, and deleting) information
	in the database is accomplished via the standard Java collections
	API. In the example, the 
    <a href="http://java.sun.com/j2se/1.5.0/docs/api/java/util/Map.html#put" target="_top">Map.put</a>
    
	method is used to add objects. All standard Java methods for
    modifying a collection may be used with the DB Java Collections API.
</p>
      <p>
    The <tt class="methodname">PopulateDatabase.doWork()</tt> method calls private methods
	for adding objects to each of the three database stores. It is
	called via the 
    <a href="../../java/com/sleepycat/collections/TransactionRunner.html" target="_top">TransactionRunner</a>
    
	class and was outlined in the previous section.
</p>
      <a id="cb_populatedatabase"></a>
      <pre class="programlisting">import java.util.Map;
import com.sleepycat.collections.TransactionWorker;
...
public class Sample
{
    ...
    private SampleViews views;
    ...
    private class PopulateDatabase implements TransactionWorker
    {
        public void doWork()
            throws Exception
        {
<b class="userinput"><tt>            addSuppliers();
            addParts();
            addShipments();</tt></b>
        }
    }
    ...

<b class="userinput"><tt>    private void addSuppliers()
    {
    }

private void addParts()
    {
    }

private void addShipments()
    {
    }</tt></b>
} </pre>
      <p>
    The <tt class="methodname">addSuppliers()</tt>, <tt class="methodname">addParts()</tt> and <tt class="methodname">addShipments()</tt>
	methods add objects to the Suppliers, Parts and Shipments stores.
	The 
    <a href="http://java.sun.com/j2se/1.5.0/docs/api/java/util/Map.html" target="_top">Map</a>
    
	for each store is obtained from the <tt class="classname">SampleViews</tt> object.
</p>
      <a id="cb_addsuppliers"></a>
      <pre class="programlisting">    private void addSuppliers()
    {
<b class="userinput"><tt>        Map suppliers = views.getSupplierMap();
        if (suppliers.isEmpty())
        {
            System.out.println("Adding Suppliers");
            suppliers.put(new SupplierKey("S1"),
                          new SupplierData("Smith", 20, "London"));
            suppliers.put(new SupplierKey("S2"),
                          new SupplierData("Jones", 10, "Paris"));
            suppliers.put(new SupplierKey("S3"),
                          new SupplierData("Blake", 30, "Paris"));
            suppliers.put(new SupplierKey("S4"),
                          new SupplierData("Clark", 20, "London"));
            suppliers.put(new SupplierKey("S5"),
                          new SupplierData("Adams", 30, "Athens"));
        }</tt></b>
    }

private void addParts()
    {
<b class="userinput"><tt>        Map parts = views.getPartMap();
        if (parts.isEmpty())
        {
            System.out.println("Adding Parts");
            parts.put(new PartKey("P1"),
                      new PartData("Nut", "Red",
                                    new Weight(12.0, Weight.GRAMS),
                                    "London"));
            parts.put(new PartKey("P2"),
                      new PartData("Bolt", "Green",
                                    new Weight(17.0, Weight.GRAMS),
                                    "Paris"));
            parts.put(new PartKey("P3"),
                      new PartData("Screw", "Blue",
                                    new Weight(17.0, Weight.GRAMS),
                                    "Rome"));
            parts.put(new PartKey("P4"),
                      new PartData("Screw", "Red",
                                    new Weight(14.0, Weight.GRAMS),
                                    "London"));
            parts.put(new PartKey("P5"),
                      new PartData("Cam", "Blue",
                                    new Weight(12.0, Weight.GRAMS),
                                    "Paris"));
            parts.put(new PartKey("P6"),
                      new PartData("Cog", "Red",
                                    new Weight(19.0, Weight.GRAMS),
                                    "London"));
        }</tt></b>
    }

private void addShipments()
    {
<b class="userinput"><tt>        Map shipments = views.getShipmentMap();
        if (shipments.isEmpty())
        {
            System.out.println("Adding Shipments");
            shipments.put(new ShipmentKey("P1", "S1"),
                          new ShipmentData(300));
            shipments.put(new ShipmentKey("P2", "S1"),
                          new ShipmentData(200));
            shipments.put(new ShipmentKey("P3", "S1"),
                          new ShipmentData(400));
            shipments.put(new ShipmentKey("P4", "S1"),
                          new ShipmentData(200));
            shipments.put(new ShipmentKey("P5", "S1"),
                          new ShipmentData(100));
            shipments.put(new ShipmentKey("P6", "S1"),
                          new ShipmentData(100));
            shipments.put(new ShipmentKey("P1", "S2"),
                          new ShipmentData(300));
            shipments.put(new ShipmentKey("P2", "S2"),
                          new ShipmentData(400));
            shipments.put(new ShipmentKey("P2", "S3"),
                          new ShipmentData(200));
            shipments.put(new ShipmentKey("P2", "S4"),
                          new ShipmentData(200));
            shipments.put(new ShipmentKey("P4", "S4"),
                          new ShipmentData(300));
            shipments.put(new ShipmentKey("P5", "S4"),
                          new ShipmentData(400));
        }</tt></b>
    } 
}</pre>
      <p>
    The key and value classes used above were defined in the
    <a href="BasicProgram.html#keyandvalueclasses">
		Defining Serialized Key and Value Classes
	</a>.
</p>
      <p>
    In each method above, objects are added only if the map is not
	empty. This is a simple way of allowing the example program to be
	run repeatedly. In real-life applications another technique —
	checking the 
    <a href="http://java.sun.com/j2se/1.5.0/docs/api/java/util/Map.html#containsKey" target="_top">Map.containsKey</a>
    
	method, for example — might be used.
</p>
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