implement a simple save method (#79)

Author: sergejsvisockis

active-record/src/main/java/com/iluwatar/activerecord/Customer.java

@@ -36,6 +36,11 @@ protected String getTableName() {
     return "customer";
   }
 
+  @Override
+  protected String constructInsertQuery() {
+    return "INSERT INTO " + getTableName() + " VALUES(?, ?, ?, ?)";
+  }
+
   @Override
   protected void setFieldsFromResultSet(ResultSet rs) throws SQLException {
     this.id = rs.getLong("id");
@@ -46,6 +51,9 @@ protected void setFieldsFromResultSet(ResultSet rs) throws SQLException {
 
   @Override
   protected void setPreparedStatementParams(PreparedStatement pstmt) throws SQLException {
-
+    pstmt.setLong(1, id);
+    pstmt.setString(2, customerNumber);
+    pstmt.setString(3, firstName);
+    pstmt.setString(4, lastName);
   }
 }

active-record/src/main/java/com/iluwatar/activerecord/Order.java

@@ -25,6 +25,11 @@ protected String getTableName() {
     return "order";
   }
 
+  @Override
+  protected String constructInsertQuery() {
+    return null;
+  }
+
   @Override
   protected void setFieldsFromResultSet(ResultSet rs) throws SQLException {
     this.id = rs.getLong("id");

active-record/src/main/java/com/iluwatar/activerecord/RecordBase.java

@@ -5,6 +5,7 @@
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
+import java.sql.Statement;
 import java.util.ArrayList;
 import java.util.List;
 import javax.sql.DataSource;
@@ -58,6 +59,13 @@ protected Connection getConnection() {
    */
   protected abstract String getTableName();
 
+  /**
+   * Constructs an INSERT query which is being used for an insertion purposes.
+   *
+   * @return an insertion query.
+   */
+  protected abstract String constructInsertQuery();
+
   /**
    * Set all the fields into the underlying domain model from the result set.
    *
@@ -85,9 +93,9 @@ public List<T> findAll() {
         PreparedStatement pstmt = conn.prepareStatement(constructFindAllQuery())) {
       try (ResultSet rs = pstmt.executeQuery()) {
         while (rs.next()) {
-          T record = getDeclaredClassInstance();
-          record.setFieldsFromResultSet(rs);
-          recordList.add(record);
+          T theRecord = getDeclaredClassInstance();
+          theRecord.setFieldsFromResultSet(rs);
+          recordList.add(theRecord);
         }
         return recordList;
       }
@@ -108,9 +116,9 @@ public T findById(Long id) {
       pstmt.setLong(1, id);
       try (ResultSet rs = pstmt.executeQuery()) {
         if (rs.next()) {
-          T record = getDeclaredClassInstance();
-          record.setFieldsFromResultSet(rs);
-          return record;
+          T theRecord = getDeclaredClassInstance();
+          theRecord.setFieldsFromResultSet(rs);
+          return theRecord;
         }
         return getDeclaredClassInstance();
       }
@@ -125,9 +133,8 @@ public T findById(Long id) {
    */
   public void save() {
     try (Connection connection = getConnection();
-        // TODO
-        PreparedStatement pstmt = connection.prepareStatement(null,
-            PreparedStatement.RETURN_GENERATED_KEYS)) {
+        PreparedStatement pstmt = connection.prepareStatement(constructInsertQuery(),
+            Statement.RETURN_GENERATED_KEYS)) {
 
       setPreparedStatementParams(pstmt);
       pstmt.executeUpdate();