ARROW-3965: JdbcToArrowConfigBuilder

java/adapter/jdbc/src/main/java/org/apache/arrow/adapter/jdbc/JdbcToArrow.java

@@ -137,7 +137,6 @@ public static VectorSchemaRoot sqlToArrow(Connection connection, String query, J
     Preconditions.checkNotNull(connection, "JDBC connection object can not be null");
     Preconditions.checkArgument(query != null && query.length() > 0, "SQL query can not be null or empty");
     Preconditions.checkNotNull(config, "The configuration cannot be null");
-    Preconditions.checkArgument(config.isValid(), "The configuration must be valid");
 
     try (Statement stmt = connection.createStatement()) {
       return sqlToArrow(stmt.executeQuery(query), config);
@@ -221,7 +220,6 @@ public static VectorSchemaRoot sqlToArrow(ResultSet resultSet, JdbcToArrowConfig
       throws SQLException, IOException {
     Preconditions.checkNotNull(resultSet, "JDBC ResultSet object can not be null");
     Preconditions.checkNotNull(config, "The configuration cannot be null");
-    Preconditions.checkArgument(config.isValid(), "The configuration must be valid");
 
     VectorSchemaRoot root = VectorSchemaRoot.create(
             JdbcToArrowUtils.jdbcToArrowSchema(resultSet.getMetaData(), config), config.getAllocator());

java/adapter/jdbc/src/main/java/org/apache/arrow/adapter/jdbc/JdbcToArrowConfig.java

@@ -46,7 +46,7 @@ public final class JdbcToArrowConfig {
    * @param allocator The memory allocator to construct the Arrow vectors with.
    * @param calendar The calendar to use when constructing Timestamp fields and reading time-based results.
    */
-  public JdbcToArrowConfig(BaseAllocator allocator, Calendar calendar) {
+  JdbcToArrowConfig(BaseAllocator allocator, Calendar calendar) {
     Preconditions.checkNotNull(allocator, "Memory allocator cannot be null");
     Preconditions.checkNotNull(calendar, "Calendar object can not be null");
 
@@ -63,49 +63,11 @@ public Calendar getCalendar() {
     return calendar;
   }
 
-  /**
-   * Sets the {@link Calendar} to use when constructing timestamp fields in the
-   * Arrow schema, and reading time-based fields from the JDBC <code>ResultSet</code>.
-   *
-   * @param calendar the calendar to set.
-   * @exception NullPointerExeption if <code>calendar</code> is <code>null</code>.
-   */
-  public JdbcToArrowConfig setCalendar(Calendar calendar) {
-    Preconditions.checkNotNull(calendar, "Calendar object can not be null");
-    this.calendar = calendar;
-    return this;
-  }
-
   /**
    * The Arrow memory allocator.
    * @return the allocator.
    */
   public BaseAllocator getAllocator() {
     return allocator;
   }
-
-  /**
-   * Sets the memory allocator to use when construting the Arrow vectors from the ResultSet.
-   *
-   * @param allocator the allocator to set.
-   * @exception NullPointerException if <code>allocator</code> is null.
-   */
-  public JdbcToArrowConfig setAllocator(BaseAllocator allocator) {
-    Preconditions.checkNotNull(allocator, "Memory allocator cannot be null");
-    this.allocator = allocator;
-    return this;
-  }
-
-  /**
-   * Whether this configuration is valid.  The configuration is valid when:
-   * <ul>
-   *   <li>A memory allocator is provided.</li>
-   *   <li>A calendar is provided.</li>
-   * </ul>
-   *
-   * @return Whether this configuration is valid.
-   */
-  public boolean isValid() {
-    return (calendar != null) && (allocator != null);
-  }
 }

java/adapter/jdbc/src/main/java/org/apache/arrow/adapter/jdbc/JdbcToArrowConfigBuilder.java

@@ -0,0 +1,71 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.arrow.adapter.jdbc;
+
+import java.util.Calendar;
+
+import org.apache.arrow.memory.BaseAllocator;
+
+import com.google.common.base.Preconditions;
+
+public class JdbcToArrowConfigBuilder {
+  private Calendar calendar;
+  private BaseAllocator allocator;
+
+  public JdbcToArrowConfigBuilder() {
+  }
+
+  public JdbcToArrowConfigBuilder(BaseAllocator allocator, Calendar calendar) {
+    this();
+
+    Preconditions.checkNotNull(allocator, "Memory allocator cannot be null");
+    Preconditions.checkNotNull(calendar, "Calendar object can not be null");
+
+    this.allocator = allocator;
+    this.calendar = calendar;
+  }
+
+  /**
+   * Sets the memory allocator to use when constructing the Arrow vectors from the ResultSet.
+   *
+   * @param allocator the allocator to set.
+   * @exception NullPointerException if <code>allocator</code> is null.
+   */
+  public JdbcToArrowConfigBuilder setAllocator(BaseAllocator allocator) {
+    Preconditions.checkNotNull(allocator, "Memory allocator cannot be null");
+    this.allocator = allocator;
+    return this;
+  }
+
+  /**
+   * Sets the {@link Calendar} to use when constructing timestamp fields in the
+   * Arrow schema, and reading time-based fields from the JDBC <code>ResultSet</code>.
+   *
+   * @param calendar the calendar to set.
+   * @exception NullPointerExeption if <code>calendar</code> is <code>null</code>.
+   */
+  public JdbcToArrowConfigBuilder setCalendar(Calendar calendar) {
+    Preconditions.checkNotNull(calendar, "Calendar object can not be null");
+    this.calendar = calendar;
+    return this;
+  }
+
+  public JdbcToArrowConfig build() {
+    return new JdbcToArrowConfig(allocator, calendar);
+  }
+}

java/adapter/jdbc/src/main/java/org/apache/arrow/adapter/jdbc/JdbcToArrowUtils.java

@@ -144,7 +144,6 @@ public static Schema jdbcToArrowSchema(ResultSetMetaData rsmd, Calendar calendar
   public static Schema jdbcToArrowSchema(ResultSetMetaData rsmd, JdbcToArrowConfig config) throws SQLException {
     Preconditions.checkNotNull(rsmd, "JDBC ResultSetMetaData object can't be null");
     Preconditions.checkNotNull(config, "The configuration object must not be null");
-    Preconditions.checkArgument(config.isValid(), "The configuration object must be valid");
 
     List<Field> fields = new ArrayList<>();
     int columnCount = rsmd.getColumnCount();
@@ -269,7 +268,6 @@ public static void jdbcToArrowVectors(ResultSet rs, VectorSchemaRoot root, JdbcT
     Preconditions.checkNotNull(rs, "JDBC ResultSet object can't be null");
     Preconditions.checkNotNull(root, "JDBC ResultSet object can't be null");
     Preconditions.checkNotNull(config, "JDBC-to-Arrow configuration cannot be null");
-    Preconditions.checkArgument(config.isValid(), "JDBC-to-Arrow configuration must be valid");
 
     ResultSetMetaData rsmd = rs.getMetaData();
     int columnCount = rsmd.getColumnCount();

java/adapter/jdbc/src/test/java/org/apache/arrow/adapter/jdbc/JdbcToArrowConfigTest.java

@@ -33,45 +33,61 @@ public class JdbcToArrowConfigTest {
   private static final Calendar calendar = Calendar.getInstance(TimeZone.getTimeZone("UTC"), Locale.ROOT);
 
   @Test(expected = NullPointerException.class)
-  public void testNullArguments() {
+  public void testConfigNullArguments() {
     new JdbcToArrowConfig(null, null);
   }
 
   @Test(expected = NullPointerException.class)
-  public void testNullCalendar() {
+  public void testBuilderNullArguments() {
+    new JdbcToArrowConfigBuilder(null, null);
+  }
+
+  @Test(expected = NullPointerException.class)
+  public void testConfigNullCalendar() {
     new JdbcToArrowConfig(allocator, null);
   }
 
   @Test(expected = NullPointerException.class)
-  public void testNullAllocator() {
+  public void testBuilderNullCalendar() {
+    new JdbcToArrowConfigBuilder(allocator, null);
+  }
+
+  @Test(expected = NullPointerException.class)
+  public void testConfigNullAllocator() {
     new JdbcToArrowConfig(null, calendar);
   }
 
+  @Test(expected = NullPointerException.class)
+  public void testBuilderNullAllocator() {
+    new JdbcToArrowConfigBuilder(null, calendar);
+  }
+
   @Test(expected = NullPointerException.class)
   public void testSetNullAllocator() {
-    JdbcToArrowConfig config = new JdbcToArrowConfig(allocator, calendar);
-    config.setAllocator(null);
+    JdbcToArrowConfigBuilder builder = new JdbcToArrowConfigBuilder(allocator, calendar);
+    builder.setAllocator(null);
   }
 
   @Test(expected = NullPointerException.class)
   public void testSetNullCalendar() {
-    JdbcToArrowConfig config = new JdbcToArrowConfig(allocator, calendar);
-    config.setCalendar(null);
+    JdbcToArrowConfigBuilder builder = new JdbcToArrowConfigBuilder(allocator, calendar);
+    builder.setCalendar(null);
   }
 
   @Test
   public void testConfig() {
-    JdbcToArrowConfig config = new JdbcToArrowConfig(allocator, calendar);
-    assertTrue(config.isValid());
+    JdbcToArrowConfigBuilder builder = new JdbcToArrowConfigBuilder(allocator, calendar);
+    JdbcToArrowConfig config = builder.build();
+
     assertTrue(allocator == config.getAllocator());
     assertTrue(calendar == config.getCalendar());
 
     Calendar newCalendar = Calendar.getInstance();
     BaseAllocator newAllocator = new RootAllocator(Integer.SIZE);
 
-    config.setAllocator(newAllocator).setCalendar(newCalendar);
+    builder.setAllocator(newAllocator).setCalendar(newCalendar);
+    config = builder.build();
 
-    assertTrue(config.isValid());
     assertTrue(newAllocator == config.getAllocator());
     assertTrue(newCalendar == config.getCalendar());
   }

java/adapter/jdbc/src/test/java/org/apache/arrow/adapter/jdbc/h2/JdbcToArrowCharSetTest.java

@@ -31,7 +31,7 @@
 
 import org.apache.arrow.adapter.jdbc.AbstractJdbcToArrowTest;
 import org.apache.arrow.adapter.jdbc.JdbcToArrow;
-import org.apache.arrow.adapter.jdbc.JdbcToArrowConfig;
+import org.apache.arrow.adapter.jdbc.JdbcToArrowConfigBuilder;
 import org.apache.arrow.adapter.jdbc.Table;
 import org.apache.arrow.memory.RootAllocator;
 import org.apache.arrow.vector.VarCharVector;
@@ -119,11 +119,11 @@ public void testJdbcToArroValues() throws SQLException, IOException {
         Calendar.getInstance()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn.createStatement().executeQuery(table.getQuery()),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn,
         table.getQuery(),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
   }
 
   /**

java/adapter/jdbc/src/test/java/org/apache/arrow/adapter/jdbc/h2/JdbcToArrowDataTypesTest.java

@@ -40,7 +40,7 @@
 
 import org.apache.arrow.adapter.jdbc.AbstractJdbcToArrowTest;
 import org.apache.arrow.adapter.jdbc.JdbcToArrow;
-import org.apache.arrow.adapter.jdbc.JdbcToArrowConfig;
+import org.apache.arrow.adapter.jdbc.JdbcToArrowConfigBuilder;
 import org.apache.arrow.adapter.jdbc.Table;
 import org.apache.arrow.memory.RootAllocator;
 import org.apache.arrow.vector.BigIntVector;
@@ -145,11 +145,11 @@ public void testJdbcToArroValues() throws SQLException, IOException {
     testDataSets(JdbcToArrow.sqlToArrow(conn.createStatement().executeQuery(table.getQuery()), Calendar.getInstance()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn.createStatement().executeQuery(table.getQuery()),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn,
         table.getQuery(),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
   }
 
   /**

java/adapter/jdbc/src/test/java/org/apache/arrow/adapter/jdbc/h2/JdbcToArrowNullTest.java

@@ -27,7 +27,7 @@
 
 import org.apache.arrow.adapter.jdbc.AbstractJdbcToArrowTest;
 import org.apache.arrow.adapter.jdbc.JdbcToArrow;
-import org.apache.arrow.adapter.jdbc.JdbcToArrowConfig;
+import org.apache.arrow.adapter.jdbc.JdbcToArrowConfigBuilder;
 import org.apache.arrow.adapter.jdbc.Table;
 import org.apache.arrow.memory.RootAllocator;
 import org.apache.arrow.vector.BigIntVector;
@@ -102,11 +102,11 @@ public void testJdbcToArroValues() throws SQLException, IOException {
     testDataSets(JdbcToArrow.sqlToArrow(conn.createStatement().executeQuery(table.getQuery()), Calendar.getInstance()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn.createStatement().executeQuery(table.getQuery()),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn,
         table.getQuery(),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
   }
 
 

java/adapter/jdbc/src/test/java/org/apache/arrow/adapter/jdbc/h2/JdbcToArrowTest.java

@@ -48,7 +48,7 @@
 
 import org.apache.arrow.adapter.jdbc.AbstractJdbcToArrowTest;
 import org.apache.arrow.adapter.jdbc.JdbcToArrow;
-import org.apache.arrow.adapter.jdbc.JdbcToArrowConfig;
+import org.apache.arrow.adapter.jdbc.JdbcToArrowConfigBuilder;
 import org.apache.arrow.adapter.jdbc.Table;
 import org.apache.arrow.memory.RootAllocator;
 import org.apache.arrow.vector.BigIntVector;
@@ -136,11 +136,11 @@ public void testJdbcToArroValues() throws SQLException, IOException {
         Calendar.getInstance()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn.createStatement().executeQuery(table.getQuery()),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn,
         table.getQuery(),
-        new JdbcToArrowConfig(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance())));
+        new JdbcToArrowConfigBuilder(new RootAllocator(Integer.MAX_VALUE), Calendar.getInstance()).build()));
   }
 
   /**

java/adapter/jdbc/src/test/java/org/apache/arrow/adapter/jdbc/h2/JdbcToArrowTimeZoneTest.java

@@ -30,7 +30,7 @@
 
 import org.apache.arrow.adapter.jdbc.AbstractJdbcToArrowTest;
 import org.apache.arrow.adapter.jdbc.JdbcToArrow;
-import org.apache.arrow.adapter.jdbc.JdbcToArrowConfig;
+import org.apache.arrow.adapter.jdbc.JdbcToArrowConfigBuilder;
 import org.apache.arrow.adapter.jdbc.Table;
 import org.apache.arrow.memory.RootAllocator;
 import org.apache.arrow.vector.DateMilliVector;
@@ -108,15 +108,15 @@ public void testJdbcToArroValues() throws SQLException, IOException {
         Calendar.getInstance(TimeZone.getTimeZone(table.getTimezone()))));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn.createStatement().executeQuery(table.getQuery()),
-        new JdbcToArrowConfig(
+        new JdbcToArrowConfigBuilder(
             new RootAllocator(Integer.MAX_VALUE),
-            Calendar.getInstance(TimeZone.getTimeZone(table.getTimezone())))));
+            Calendar.getInstance(TimeZone.getTimeZone(table.getTimezone()))).build()));
     testDataSets(JdbcToArrow.sqlToArrow(
         conn,
         table.getQuery(),
-        new JdbcToArrowConfig(
+        new JdbcToArrowConfigBuilder(
             new RootAllocator(Integer.MAX_VALUE),
-            Calendar.getInstance(TimeZone.getTimeZone(table.getTimezone())))));
+            Calendar.getInstance(TimeZone.getTimeZone(table.getTimezone()))).build()));
   }
 
   /**