SqlParameterSourceUtils.createBatch with Collection support

Issue: SPR-16215

Author: jhoeller

spring-jdbc/src/main/java/org/springframework/jdbc/core/BatchUpdateUtils.java

@@ -23,8 +23,8 @@
 import org.springframework.lang.Nullable;
 
 /**
- * Generic utility methods for working with JDBC batch statements. Mainly for internal use
- * within the framework.
+ * Generic utility methods for working with JDBC batch statements.
+ * Mainly for internal use within the framework.
  *
  * @author Thomas Risberg
  * @since 3.0

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/NamedParameterJdbcTemplate.java

@@ -337,13 +337,7 @@ public int update(
 
 	@Override
 	public int[] batchUpdate(String sql, Map<String, ?>[] batchValues) {
-		SqlParameterSource[] batchArgs = new SqlParameterSource[batchValues.length];
-		int i = 0;
-		for (Map<String, ?> values : batchValues) {
-			batchArgs[i] = new MapSqlParameterSource(values);
-			i++;
-		}
-		return batchUpdate(sql, batchArgs);
+		return batchUpdate(sql, SqlParameterSourceUtils.createBatch(batchValues));
 	}
 
 	@Override

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/SqlParameterSourceUtils.java

@@ -16,54 +16,81 @@
 
 package org.springframework.jdbc.core.namedparam;
 
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 
 import org.springframework.jdbc.core.SqlParameterValue;
 import org.springframework.lang.Nullable;
 
 /**
- * Class that provides helper methods for the use of {@link SqlParameterSource}
- * with {@code SimpleJdbc} classes.
+ * Class that provides helper methods for the use of {@link SqlParameterSource},
+ * in particular with {@link NamedParameterJdbcTemplate}.
  *
  * @author Thomas Risberg
+ * @author Juergen Hoeller
  * @since 2.5
  */
-public class SqlParameterSourceUtils {
+public abstract class SqlParameterSourceUtils {
 
 	/**
-	 * Create an array of MapSqlParameterSource objects populated with data from the
-	 * values passed in. This will define what is included in a batch operation.
-	 * @param valueMaps array of Maps containing the values to be used
-	 * @return an array of SqlParameterSource
+	 * Create an array of {@link SqlParameterSource} objects populated with data
+	 * from the values passed in (either a {@link Map} or a bean object).
+	 * This will define what is included in a batch operation.
+	 * @param candidates object array of objects containing the values to be used
+	 * @return an array of {@link SqlParameterSource}
+	 * @see MapSqlParameterSource
+	 * @see BeanPropertySqlParameterSource
+	 * @see NamedParameterJdbcTemplate#batchUpdate(String, SqlParameterSource[]))
 	 */
-	public static SqlParameterSource[] createBatch(Map<String, ?>[] valueMaps) {
-		MapSqlParameterSource[] batch = new MapSqlParameterSource[valueMaps.length];
-		for (int i = 0; i < valueMaps.length; i++) {
-			Map<String, ?> valueMap = valueMaps[i];
-			batch[i] = new MapSqlParameterSource(valueMap);
+	@SuppressWarnings("unchecked")
+	public static SqlParameterSource[] createBatch(Object... candidates) {
+		return createBatch(Arrays.asList(candidates));
+	}
+
+	/**
+	 * Create an array of {@link SqlParameterSource} objects populated with data
+	 * from the values passed in (either a {@link Map} or a bean object).
+	 * This will define what is included in a batch operation.
+	 * @param candidates collection of objects containing the values to be used
+	 * @return an array of {@link SqlParameterSource}
+	 * @since 5.0.2
+	 * @see MapSqlParameterSource
+	 * @see BeanPropertySqlParameterSource
+	 * @see NamedParameterJdbcTemplate#batchUpdate(String, SqlParameterSource[]))
+	 */
+	@SuppressWarnings("unchecked")
+	public static SqlParameterSource[] createBatch(Collection<?> candidates) {
+		SqlParameterSource[] batch = new SqlParameterSource[candidates.size()];
+		int i = 0;
+		for (Object candidate : candidates) {
+			batch[i] = (candidate instanceof Map ? new MapSqlParameterSource((Map<String, ?>) candidate) :
+					new BeanPropertySqlParameterSource(candidate));
+			i++;
 		}
 		return batch;
 	}
 
 	/**
-	 * Create an array of BeanPropertySqlParameterSource objects populated with data
-	 * from the values passed in. This will define what is included in a batch operation.
-	 * @param beans object array of beans containing the values to be used
-	 * @return an array of SqlParameterSource
+	 * Create an array of {@link MapSqlParameterSource} objects populated with data from
+	 * the values passed in. This will define what is included in a batch operation.
+	 * @param valueMaps array of {@link Map} instances containing the values to be used
+	 * @return an array of {@link SqlParameterSource}
+	 * @see MapSqlParameterSource
+	 * @see NamedParameterJdbcTemplate#batchUpdate(String, Map[])
 	 */
-	public static SqlParameterSource[] createBatch(Object[] beans) {
-		BeanPropertySqlParameterSource[] batch = new BeanPropertySqlParameterSource[beans.length];
-		for (int i = 0; i < beans.length; i++) {
-			Object bean = beans[i];
-			batch[i] = new BeanPropertySqlParameterSource(bean);
+	public static SqlParameterSource[] createBatch(Map<String, ?>[] valueMaps) {
+		SqlParameterSource[] batch = new SqlParameterSource[valueMaps.length];
+		for (int i = 0; i < valueMaps.length; i++) {
+			batch[i] = new MapSqlParameterSource(valueMaps[i]);
 		}
 		return batch;
 	}
 
 	/**
 	 * Create a wrapped value if parameter has type information, plain object if not.
-	 * @param source the source of paramer values and type information
+	 * @param source the source of parameter values and type information
 	 * @param parameterName the name of the parameter
 	 * @return the value object
 	 */
@@ -85,13 +112,13 @@ public static Object getTypedValue(SqlParameterSource source, String parameterNa
 
 	/**
 	 * Create a Map of case insensitive parameter names together with the original name.
-	 * @param parameterSource the source of paramer names
+	 * @param parameterSource the source of parameter names
 	 * @return the Map that can be used for case insensitive matching of parameter names
 	 */
 	public static Map<String, String> extractCaseInsensitiveParameterNames(SqlParameterSource parameterSource) {
 		Map<String, String> caseInsensitiveParameterNames = new HashMap<>();
 		if (parameterSource instanceof BeanPropertySqlParameterSource) {
-			String[] propertyNames = ((BeanPropertySqlParameterSource)parameterSource).getReadablePropertyNames();
+			String[] propertyNames = ((BeanPropertySqlParameterSource) parameterSource).getReadablePropertyNames();
 			for (String name : propertyNames) {
 				caseInsensitiveParameterNames.put(name.toLowerCase(), name);
 			}