Add a run-time namespace placeholder using system properties tests. (#89)

Author: roimenashe

src/test/java/com/aerospike/mapper/NamespacePlaceHolderTest.java

@@ -0,0 +1,60 @@
+package com.aerospike.mapper;
+
+import com.aerospike.client.AerospikeException;
+import com.aerospike.mapper.annotations.AerospikeKey;
+import com.aerospike.mapper.annotations.AerospikeRecord;
+import com.aerospike.mapper.tools.AeroMapper;
+import org.junit.jupiter.api.Test;
+
+import java.util.Properties;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class NamespacePlaceHolderTest extends AeroMapperBaseTest {
+
+    @AerospikeRecord(namespace = "${namespace.name:default}", set = "set1")
+    public static class PlaceHolderModel {
+
+        @AerospikeKey
+        String id;
+        String name;
+        String email;
+    }
+
+    @Test
+    public void shouldSave() {
+        Properties props = System.getProperties();
+        props.setProperty("namespace.name", "test");
+
+        PlaceHolderModel placeHolderModel1 = new PlaceHolderModel();
+        placeHolderModel1.id = "id1";
+        placeHolderModel1.name = "name1";
+        placeHolderModel1.email = "[email protected]";
+
+        AeroMapper mapper = new AeroMapper.Builder(client).build();
+        mapper.save(placeHolderModel1);
+
+        PlaceHolderModel placeHolderModelRead = mapper.read(PlaceHolderModel.class, placeHolderModel1.id);
+        assertEquals(placeHolderModel1.email, placeHolderModelRead.email);
+    }
+
+    @Test
+    public void shouldFailOnNonExistingNamespace() {
+        Properties props = System.getProperties();
+        props.setProperty("namespace.name", "non-existing-namespace");
+
+        PlaceHolderModel placeHolderModel1 = new PlaceHolderModel();
+        placeHolderModel1.id = "id1";
+        placeHolderModel1.name = "name1";
+        placeHolderModel1.email = "[email protected]";
+
+        AeroMapper mapper = new AeroMapper.Builder(client).build();
+
+        try {
+            mapper.save(placeHolderModel1);
+            fail();
+        } catch (AerospikeException ae) {
+            assertTrue(true);
+        }
+    }
+}