Add DatabaseUtils unit tests

Author: sbabcoc

.gitignore

@@ -1,14 +1,17 @@
-.settings
-target
-.classpath
-.project
-*~
-*.tmproj
-*.iml
-.idea
-.scala_dependencies
-integration/bundle/
-integration/felix-cache/
-runner
-.DS_Store
-test-output
+.settings
+target
+.classpath
+.project
+*~
+*.tmproj
+*.iml
+.idea
+.scala_dependencies
+integration/bundle/
+integration/felix-cache/
+runner
+.DS_Store
+test-output
+@TestDB
+TestDB
+derby*

pom.xml

@@ -35,6 +35,7 @@
     <gpg-plugin.version>1.6</gpg-plugin.version>
     <staging-plugin.version>1.6.7</staging-plugin.version>
     <release-plugin.version>2.5.3</release-plugin.version>
+    <apache-derby.version>10.14.1.0</apache-derby.version>
     <skipSigning>true</skipSigning>
   </properties>
 
@@ -63,6 +64,11 @@
         <artifactId>testng</artifactId>
         <version>${testng.version}</version>
       </dependency>
+      <dependency>
+        <groupId>org.apache.derby</groupId>
+        <artifactId>derby</artifactId>
+        <version>${apache-derby.version}</version>
+      </dependency>
     </dependencies>
   </dependencyManagement>
 
@@ -72,6 +78,11 @@
       <artifactId>testng</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.apache.derby</groupId>
+      <artifactId>derby</artifactId>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>

src/main/java/com/nordstrom/common/jdbc/DatabaseUtils.java

@@ -1,30 +1,33 @@
 package com.nordstrom.common.jdbc;
 
 import java.sql.Connection;
+import java.sql.Driver;
 import java.sql.DriverManager;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.Arrays;
+import java.util.Iterator;
+import java.util.ServiceLoader;
 
 import com.nordstrom.common.base.UncheckedThrow;
 
 import java.sql.PreparedStatement;
 
 /**
- * This utility class provides facilities that enable you to define collections of Oracle database queries and
+ * This utility class provides facilities that enable you to define collections of database queries and
  * execute them easily. Query collections are defined as Java enumeration that implement the {@link QueryAPI}
  * interface: <ul>
  * <li>{@link QueryAPI#getQueryStr() getQueryStr} - Get the query string for this constant. This is the actual query
  *     that's sent to the database.</li>
  * <li>{@link QueryAPI#getArgNames() getArgNames} - Get the names of the arguments for this query. This provides
  *     diagnostic information if the incorrect number of arguments is specified by the client.</li>
  * <li>{@link QueryAPI#getArgCount() getArgCount} - Get the number of arguments required by this query. This enables
- *     {@link #executeOracleQuery(Class, QueryAPI, Object[])} to verify that the correct number of arguments has been
+ *     {@link #executeQuery(Class, QueryAPI, Object[])} to verify that the correct number of arguments has been
  *     specified by the client.</li>
  * <li>{@link QueryAPI#getConnection() getConnection} - Get the connection string associated with this query. This
  *     eliminates the need for the client to provide this information.</li>
  * <li>{@link QueryAPI#getEnum() getEnum} - Get the enumeration to which this query belongs. This enables {@link 
- *     #executeOracleQuery(Class, QueryAPI, Object[])} to retrieve the name of the query's enumerated constant for
+ *     #executeQuery(Class, QueryAPI, Object[])} to retrieve the name of the query's enumerated constant for
  *     diagnostic messages.</li>
  * </ul>
  *
@@ -173,10 +176,9 @@ private DatabaseUtils() {
     }
 
     static {
-        try {
-            Class.forName("oracle.jdbc.driver.OracleDriver");
-        } catch (ClassNotFoundException e) {
-            throw new RuntimeException("Unable to load the Oracle JDBC driver", e);
+        Iterator<Driver> iterator = ServiceLoader.load(Driver.class).iterator();
+        while (iterator.hasNext()) {
+            iterator.next();
         }
     }
 
@@ -188,7 +190,7 @@ private DatabaseUtils() {
      * @return count of records updated
      */
     public static int update(QueryAPI query, Object... queryArgs) {
-        Integer result = (Integer) executeOracleQuery(null, query, queryArgs);
+        Integer result = (Integer) executeQuery(null, query, queryArgs);
         return (result != null) ? result.intValue() : -1;
     }
 
@@ -200,7 +202,7 @@ public static int update(QueryAPI query, Object... queryArgs) {
      * @return row 1 / column 1 as integer; -1 if no rows were returned
      */
     public static int getInt(QueryAPI query, Object... queryArgs) {
-        Integer result = (Integer) executeOracleQuery(Integer.class, query, queryArgs);
+        Integer result = (Integer) executeQuery(Integer.class, query, queryArgs);
         return (result != null) ? result.intValue() : -1;
     }
 
@@ -212,7 +214,7 @@ public static int getInt(QueryAPI query, Object... queryArgs) {
      * @return row 1 / column 1 as string; 'null' if no rows were returned
      */
     public static String getString(QueryAPI query, Object... queryArgs) {
-        return (String) executeOracleQuery(String.class, query, queryArgs);
+        return (String) executeQuery(String.class, query, queryArgs);
     }
 
     /**
@@ -223,7 +225,7 @@ public static String getString(QueryAPI query, Object... queryArgs) {
      * @return {@link ResultPackage} object
      */
     public static ResultPackage getResultPackage(QueryAPI query, Object... queryArgs) {
-        return (ResultPackage) executeOracleQuery(ResultPackage.class, query, queryArgs);
+        return (ResultPackage) executeQuery(ResultPackage.class, query, queryArgs);
     }
 
     /**
@@ -243,7 +245,7 @@ public static ResultPackage getResultPackage(QueryAPI query, Object... queryArgs
      * <b>NOTE</b>: If you specify {@link ResultPackage} as the result type, it's recommended that you close this object
      * when you're done with it to free up database and JDBC resources that were allocated for it. 
      */
-    private static Object executeOracleQuery(Class<?> resultType, QueryAPI query, Object... queryArgs) {
+    private static Object executeQuery(Class<?> resultType, QueryAPI query, Object... queryArgs) {
         int expectCount = query.getArgCount();
         int actualCount = queryArgs.length;
 
@@ -260,7 +262,7 @@ private static Object executeOracleQuery(Class<?> resultType, QueryAPI query, Ob
             throw new IllegalArgumentException(message);
         }
 
-        return executeOracleQuery(resultType, query.getConnection(), query.getQueryStr(), queryArgs);
+        return executeQuery(resultType, query.getConnection(), query.getQueryStr(), queryArgs);
     }
 
     /**
@@ -274,14 +276,14 @@ private static Object executeOracleQuery(Class<?> resultType, QueryAPI query, Ob
      * <li>For other types, {@link ResultSet#getObject(int, Class)} to return row 1 / column 1 as that type</li></ul>
      * 
      * @param resultType desired result type (see TYPES above)
-     * @param connectionStr Oracle database connection string
+     * @param connectionStr database connection string
      * @param queryStr a SQL statement that may contain one or more '?' IN parameter placeholders
      * @param param an array of objects containing the input parameter values
      * @return for update operations, the number of rows affected; for query operations, an object of the indicated type<br>
      * <b>NOTE</b>: If you specify {@link ResultPackage} as the result type, it's recommended that you close this object
      * when you're done with it to free up database and JDBC resources that were allocated for it. 
      */
-    public static Object executeOracleQuery(Class<?> resultType, String connectionStr, String queryStr, Object... param) {
+    public static Object executeQuery(Class<?> resultType, String connectionStr, String queryStr, Object... param) {
         Object result = null;
         boolean failed = false;
 
@@ -290,7 +292,7 @@ public static Object executeOracleQuery(Class<?> resultType, String connectionSt
         ResultSet resultSet = null;
 
         try {
-            connection = getOracleConnection(connectionStr);
+            connection = getConnection(connectionStr);
             statement = connection.prepareStatement(queryStr); //NOSONAR
 
             for (int i = 0; i < param.length; i++) {
@@ -321,18 +323,24 @@ public static Object executeOracleQuery(Class<?> resultType, String connectionSt
                 if (resultSet != null) {
                     try {
                         resultSet.close();
-                    } catch (SQLException e) { }
+                    } catch (SQLException e) {
+                        // Suppress shutdown failures
+                    }
                 }
                 if (statement != null) {
                     try {
                         statement.close();
-                    } catch (SQLException e) { }
+                    } catch (SQLException e) {
+                        // Suppress shutdown failures
+                    }
                 }
                 if (connection != null) {
                     try {
                         connection.commit();
                         connection.close();
-                    } catch (SQLException e) { }
+                    } catch (SQLException e) {
+                        // Suppress shutdown failures
+                    }
                 }
             }
         }
@@ -341,43 +349,19 @@ public static Object executeOracleQuery(Class<?> resultType, String connectionSt
     }
 
     /**
-     * Get a connection to the Oracle database associated with the specified connection string.
+     * Get a connection to the database associated with the specified connection string.
      * 
-     * @param connectionString Oracle database connection string
-     * @return Oracle database connection object
+     * @param connectionString database connection string
+     * @return database connection object
      */
-    private static Connection getOracleConnection(String connectionString) {
+    private static Connection getConnection(String connectionString) {
         try {
-            QueryCreds creds = new QueryCreds(connectionString);
-            return DriverManager.getConnection(creds.url, creds.userId, creds.password);
+            return DriverManager.getConnection(connectionString);
         } catch (SQLException e) {
             throw UncheckedThrow.throwUnchecked(e);
         }
     }
 
-    /**
-     * This class encapsulated database query credentials.
-     */
-    private static class QueryCreds {
-        
-        private String url;
-        private String userId;
-        private String password;
-        
-        /**
-         * Constructor for database query credentials.
-         * 
-         * @param connectionString database connection string
-         */
-        private QueryCreds(String connectionString) {
-            String[] bits = connectionString.split(";");
-            
-            url = bits[0].trim();
-            userId = bits[1].split("=")[1].trim();
-            password = bits[2].split("=")[1].trim();
-        }
-    }
-    
     /**
      * This interface defines the API supported by database query collections
      */
@@ -416,7 +400,7 @@ public interface QueryAPI {
          * 
          * @return query object enumerated constant
          */
-        Enum<?> getEnum();
+        Enum<? extends QueryAPI> getEnum(); //NOSONAR
     }
 
     /**