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32            <h2 class="title" style="clear: both"><a id="simpleput"></a>Placing Objects in an Entity Store</h2>
33          </div>
34        </div>
35      </div>
36      <p>
37                    In order to place an object in a DPL entity store,
38                    you must:
39            </p>
40      <div class="orderedlist">
41        <ol type="1">
42          <li>
43            <p>
44                                    Open the environment and store.
45                            </p>
46          </li>
47          <li>
48            <p>
49                                    Instantiate the object.
50                            </p>
51          </li>
52          <li>
53            <p>
54                                    Put the object to the store using the
55                                    <code class="methodname">put()</code> method
56                                    for the object's primary index.
57                            </p>
58          </li>
59        </ol>
60      </div>
61      <p>
62                    The following example uses the <code class="classname">SimpleDA</code>
63                    class that we show in <a class="xref" href="simpleda.html" title="SimpleDA.class">SimpleDA.class</a> to put a
64                    <code class="classname">SimpleEntityClass</code> object (see
65                    <a class="xref" href="persist_access.html#simpleentity" title="A Simple Entity Class">A Simple Entity Class</a>) to the
66                    entity store.
67            </p>
68      <p>
69                To begin, we import the Java classes that our example
70                needs. We also instantiate the private data members that we
71                require.
72           </p>
73      <pre class="programlisting">package persist.gettingStarted;
74
75import java.io.File;
76import java.io.FileNotFoundException;
77
78import com.sleepycat.db.DatabaseException;
79import com.sleepycat.db.Environment;
80import com.sleepycat.db.EnvironmentConfig;
81
82import com.sleepycat.persist.EntityStore;
83import com.sleepycat.persist.StoreConfig; 
84
85public class SimpleStorePut {
86
87    private static File envHome = new File("./JEDB");
88
89    private Environment envmnt;
90    private EntityStore store;
91    private SimpleDA sda; </pre>
92      <p>
93            Next we create a method that simply opens our database
94            environment and entity store for us. 
95    </p>
96      <pre class="programlisting">   // The setup() method opens the environment and store
97    // for us.
98    public void setup()
99        throws DatabaseException {
100
101        EnvironmentConfig envConfig = new EnvironmentConfig();
102        StoreConfig storeConfig = new StoreConfig();
103
104        envConfig.setAllowCreate(true);
105        storeConfig.setAllowCreate(true);
106
107        try {
108            // Open the environment and entity store
109            envmnt = new Environment(envHome, envConfig);
110            store = new EntityStore(envmnt, "EntityStore", storeConfig);
111        } catch (FileNotFoundException fnfe) {
112            System.err.println("setup(): " + fnfe.toString());
113            System.exit(-1);
114        }
115    } </pre>
116      <p>
117            We also need a method to close our environment and store.
118    </p>
119      <pre class="programlisting">    // Close our environment and store.
120    public void shutdown()
121        throws DatabaseException {
122
123        store.close();
124        envmnt.close();
125    } </pre>
126      <p>
127            Now we need to create a method to actually write objects to our
128            store. This method creates a <code class="classname">SimpleDA</code>
129            object (see <a class="xref" href="simpleda.html" title="SimpleDA.class">SimpleDA.class</a> that we
130            will use to access our indexes. Then we instantiate a serious
131            of <code class="classname">SimpleEntityClass</code> (see <a class="xref" href="persist_access.html#simpleentity" title="A Simple Entity Class">A Simple Entity Class</a>) 
132            instances that we
133            will place in our store. Finally, we use our primary index
134            (obtained from the <code class="classname">SimpleDA</code> class
135            instance) to actually place these objects in our store.
136    </p>
137      <p>
138            In <a class="xref" href="simpleget.html" title="Retrieving Objects from an Entity Store">Retrieving Objects from an Entity Store</a>
139            we show a class that is used to retrieve these objects.
140    </p>
141      <pre class="programlisting">    // Populate the entity store
142    private void run()
143        throws DatabaseException {
144
145        setup();
146
147        // Open the data accessor. This is used to store
148        // persistent objects.
149        sda = new SimpleDA(store);
150
151        // Instantiate and store some entity classes
152        SimpleEntityClass sec1 = new SimpleEntityClass();
153        SimpleEntityClass sec2 = new SimpleEntityClass();
154        SimpleEntityClass sec3 = new SimpleEntityClass();
155        SimpleEntityClass sec4 = new SimpleEntityClass();
156        SimpleEntityClass sec5 = new SimpleEntityClass();
157
158        sec1.setPKey("keyone");
159        sec1.setSKey("skeyone");
160
161        sec2.setPKey("keytwo");
162        sec2.setSKey("skeyone");
163
164        sec3.setPKey("keythree");
165        sec3.setSKey("skeytwo");
166
167        sec4.setPKey("keyfour");
168        sec4.setSKey("skeythree");
169
170        sec5.setPKey("keyfive");
171        sec5.setSKey("skeyfour");
172
173        sda.pIdx.put(sec1);
174        sda.pIdx.put(sec2);
175        sda.pIdx.put(sec3);
176        sda.pIdx.put(sec4);
177        sda.pIdx.put(sec5);
178
179        shutdown();
180    } </pre>
181      <p>
182            Finally, to complete our class, we need a
183            <code class="methodname">main()</code> method, which simply calls our
184            <code class="methodname">run()</code> method.
185    </p>
186      <pre class="programlisting">    // main
187    public static void main(String args[]) {
188        SimpleStorePut ssp = new SimpleStorePut();
189        try {
190            ssp.run();
191        } catch (DatabaseException dbe) {
192            System.err.println("SimpleStorePut: " + dbe.toString());
193            dbe.printStackTrace();
194        } catch (Exception e) {
195            System.out.println("Exception: " + e.toString());
196            e.printStackTrace();
197        }
198        System.out.println("All done.");
199    }
200
201} </pre>
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