Load database properties from file

src/de/unipotsdam/cs/toolup/database/ToolUpProperties.java

 package de.unipotsdam.cs.toolup.database;
 
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.InvalidPropertiesFormatException;
+import java.util.Properties;
+
 public class ToolUpProperties {
 
 	private static final String DB_USERNAME = "root";
@@ -8,9 +15,30 @@ public class ToolUpProperties {
 	private static final String SERVER_ADRESS = "localhost";
 	private static final String DATABASE_CONNECTOR = "jdbc:mysql://";
 	private static final String DB_PASSWORD = "";
+	private static String DATABASE_URL = null;
+	private static Properties PROPERTIES = null;
+	
+	static File PROPERTIES_FILE = new File("Tool.UP_cfg.xml");
 
 	public static String getDatabaseUrl() {
-		return DATABASE_CONNECTOR+SERVER_ADRESS+":"+SERVER_PORT+"/"+DB_SCHEMA+"?user="+DB_USERNAME+"&pw=" + DB_PASSWORD;
+		if (DATABASE_URL == null){
+			DATABASE_URL = DATABASE_CONNECTOR+SERVER_ADRESS+":"+SERVER_PORT+"/"+DB_SCHEMA+"?user="+DB_USERNAME+"&pw=" + DB_PASSWORD;
+		}
+		return DATABASE_URL;
+	}
+
+	public static Properties getProperties() throws InvalidPropertiesFormatException, FileNotFoundException, IOException {
+		if (PROPERTIES == null){
+			loadPropertiesFromFile();
+		}
+		return PROPERTIES;
+	}
+
+	private static synchronized void loadPropertiesFromFile() throws InvalidPropertiesFormatException, FileNotFoundException, IOException {
+		if (PROPERTIES == null){
+			PROPERTIES = new Properties(); 
+			PROPERTIES.loadFromXML(new FileInputStream(PROPERTIES_FILE));		
+		}
 	}
 
 }

test/de/unipotsdam/cs/toolup/database/ToolUpPropertiesTest.java

+package de.unipotsdam.cs.toolup.database;
+
+import static org.testng.AssertJUnit.assertEquals;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.InvalidPropertiesFormatException;
+import java.util.Properties;
+
+import org.testng.annotations.BeforeMethod;
+import org.testng.annotations.Test;
+
+public class ToolUpPropertiesTest {
+
+	private static final String KEY_SERVERADRESS = "database server adress";
+	private static final String VALUE_SERVERADRESS = "localhost";
+	private static final String KEY_SERVERPORT = "database server port";
+	private static final Object VALUE_SERVERPORT = "3306";
+	private static final String KEY_USERNAME = "database user name";
+	private static final String VALUE_USERNAME = "root";
+	private static final String KEY_PASSWORD = "database password";
+	private static final String VALUE_PASSWORD = "";
+	private static final String KEY_SCHEMA = "database schema";
+	private static final String VALUE_SCHEMA = "test";
+	
+	File PROPERTIES_FILE = new File("Tool.UP_cfg_template.xml");
+	
+	@BeforeMethod
+	public void prepareConfigFile() throws FileNotFoundException, IOException{
+		Properties props = new Properties();
+		props.put(KEY_SERVERADRESS, VALUE_SERVERADRESS);
+		props.put(KEY_SERVERPORT, VALUE_SERVERPORT);
+		props.put(KEY_USERNAME, VALUE_USERNAME);
+		props.put(KEY_PASSWORD, VALUE_PASSWORD);
+		props.put(KEY_SCHEMA, VALUE_SCHEMA);
+		props.storeToXML(new FileOutputStream(PROPERTIES_FILE), null, "utf-8");
+	}
+	
+	@Test
+	public void testThatPropertiesAreLoaded() throws InvalidPropertiesFormatException, FileNotFoundException, IOException {
+		//arrange
+
+		//act
+		Properties props = ToolUpProperties.getProperties();
+		
+		//assert
+		assertEquals(VALUE_SERVERADRESS,props.getProperty(KEY_SERVERADRESS));
+		assertEquals(VALUE_SERVERPORT,props.getProperty(KEY_SERVERPORT));
+		assertEquals(VALUE_USERNAME,props.getProperty(KEY_USERNAME));
+		assertEquals(VALUE_PASSWORD,props.getProperty(KEY_PASSWORD));
+		assertEquals(VALUE_SCHEMA,props.getProperty(KEY_SCHEMA));
+	}
+	
+	
+}