Add Utilities to Support MyBatis Spring batch

pom.xml

@@ -15,7 +15,16 @@
        limitations under the License.
 
 -->
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<!-- Copyright 2016-2019 the original author or authors. Licensed 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. -->
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
     <groupId>org.mybatis</groupId>
@@ -38,7 +47,7 @@
     <clirr.comparisonVersion>1.1.0</clirr.comparisonVersion>
     <module.name>org.mybatis.dynamic.sql</module.name>
   </properties>
-  
+
   <build>
     <pluginManagement>
       <plugins>
@@ -52,7 +61,7 @@
       </plugins>
     </pluginManagement>
   </build>
-  
+
   <reporting>
     <plugins>
       <plugin>
@@ -64,7 +73,7 @@
       </plugin>
     </plugins>
   </reporting>
-  
+
   <dependencies>
     <dependency>
       <groupId>org.junit.jupiter</groupId>
@@ -84,7 +93,7 @@
       <version>${junit.platform.version}</version>
       <scope>test</scope>
     </dependency>
-    
+
     <dependency>
       <groupId>org.assertj</groupId>
       <artifactId>assertj-core</artifactId>
@@ -97,6 +106,12 @@
       <version>3.5.0</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.mybatis</groupId>
+      <artifactId>mybatis-spring</artifactId>
+      <version>2.0.0</version>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>org.hsqldb</groupId>
       <artifactId>hsqldb</artifactId>
@@ -109,6 +124,24 @@
       <version>5.1.4.RELEASE</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.springframework.batch</groupId>
+      <artifactId>spring-batch-core</artifactId>
+      <version>4.1.1.RELEASE</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.batch</groupId>
+      <artifactId>spring-batch-test</artifactId>
+      <version>4.1.1.RELEASE</version>
+      <scope>test</scope>
+      <exclusions>
+        <exclusion>
+          <groupId>junit</groupId>
+          <artifactId>junit</artifactId>
+        </exclusion>
+      </exclusions>
+    </dependency>
     <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-classic</artifactId>
@@ -138,7 +171,7 @@
       <url>git:ssh://[email protected]/mybatis/mybatis-dynamic-sql.git?gh-pages#</url>
     </site>
   </distributionManagement>
-  
+
   <profiles>
     <profile>
       <id>javadocVersion</id>

src/main/java/org/mybatis/dynamic/sql/util/ValueMapping.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2017 the original author or authors.
+ *    Copyright 2016-2019 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -23,8 +23,9 @@ public class ValueMapping<T> extends AbstractColumnMapping implements UpdateMapp
 
     private Supplier<T> valueSupplier;
 
-    private ValueMapping(SqlColumn<T> column) {
+    private ValueMapping(SqlColumn<T> column, Supplier<T> valueSupplier) {
         super(column);
+        this.valueSupplier = valueSupplier;
     }
 
     public T value() {
@@ -37,8 +38,6 @@ public <R> R accept(UpdateMappingVisitor<R> visitor) {
     }
 
     public static <T> ValueMapping<T> of(SqlColumn<T> column, Supplier<T> valueSupplier) {
-        ValueMapping<T> mapping = new ValueMapping<>(column);
-        mapping.valueSupplier = valueSupplier;
-        return mapping;
+        return new ValueMapping<>(column, valueSupplier);
     }
 }

src/main/java/org/mybatis/dynamic/sql/util/springbatch/SpringBatchCursorReaderSelectModel.java

@@ -0,0 +1,32 @@
+/**
+ *    Copyright 2016-2019 the original author or authors.
+ *
+ *    Licensed 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.mybatis.dynamic.sql.util.springbatch;
+
+import org.mybatis.dynamic.sql.select.SelectModel;
+import org.mybatis.dynamic.sql.select.render.SelectStatementProvider;
+
+public class SpringBatchCursorReaderSelectModel {
+
+    private SelectModel selectModel;
+
+    public SpringBatchCursorReaderSelectModel(SelectModel selectModel) {
+        this.selectModel = selectModel;
+    }
+
+    public SelectStatementProvider render() {
+        return selectModel.render(SpringBatchUtility.SPRING_BATCH_READER_RENDERING_STRATEGY);
+    }
+}

src/main/java/org/mybatis/dynamic/sql/util/springbatch/SpringBatchPagingReaderSelectModel.java

@@ -0,0 +1,59 @@
+/**
+ *    Copyright 2016-2019 the original author or authors.
+ *
+ *    Licensed 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.mybatis.dynamic.sql.util.springbatch;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.mybatis.dynamic.sql.select.SelectModel;
+import org.mybatis.dynamic.sql.select.render.SelectStatementProvider;
+
+public class SpringBatchPagingReaderSelectModel {
+
+    private SelectModel selectModel;
+
+    public SpringBatchPagingReaderSelectModel(SelectModel selectModel) {
+        this.selectModel = selectModel;
+    }
+
+    public SelectStatementProvider render() {
+        SelectStatementProvider selectStatement =
+                selectModel.render(SpringBatchUtility.SPRING_BATCH_READER_RENDERING_STRATEGY);
+        return new LimitAndOffsetDecorator(selectStatement);
+    }
+
+    public class LimitAndOffsetDecorator implements SelectStatementProvider {
+        private Map<String, Object> parameters = new HashMap<>();
+        private String selectStatement;
+
+        public LimitAndOffsetDecorator(SelectStatementProvider delegate) {
+            parameters.putAll(delegate.getParameters());
+
+            selectStatement = delegate.getSelectStatement()
+                    + " LIMIT #{_pagesize} OFFSET #{_skiprows}"; //$NON-NLS-1$
+        }
+
+        @Override
+        public Map<String, Object> getParameters() {
+            return parameters;
+        }
+
+        @Override
+        public String getSelectStatement() {
+            return selectStatement;
+        }
+    }
+}

src/main/java/org/mybatis/dynamic/sql/util/springbatch/SpringBatchProviderAdapter.java

@@ -0,0 +1,29 @@
+/**
+ *    Copyright 2016-2019 the original author or authors.
+ *
+ *    Licensed 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.mybatis.dynamic.sql.util.springbatch;
+
+import java.util.Map;
+
+import org.mybatis.dynamic.sql.select.render.SelectStatementProvider;
+
+public class SpringBatchProviderAdapter {
+
+    public String select(Map<String, Object> parameterValues) {
+        SelectStatementProvider selectStatement =
+                (SelectStatementProvider) parameterValues.get(SpringBatchUtility.PARAMETER_KEY);
+        return selectStatement.getSelectStatement();
+    }
+}

src/main/java/org/mybatis/dynamic/sql/util/springbatch/SpringBatchReaderRenderingStrategy.java

@@ -0,0 +1,34 @@
+/**
+ *    Copyright 2016-2019 the original author or authors.
+ *
+ *    Licensed 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.mybatis.dynamic.sql.util.springbatch;
+
+import org.mybatis.dynamic.sql.BindableColumn;
+import org.mybatis.dynamic.sql.render.MyBatis3RenderingStrategy;
+
+/**
+ * This rendering strategy should be used for MyBatis3 statements using one of the 
+ * Spring batch readers supplied by mybatis-spring integration (http://www.mybatis.org/spring/).
+ * Those readers are MyBatisPagingItemReader and MyBatisCursorItemReader.
+ *
+ */
+public class SpringBatchReaderRenderingStrategy extends MyBatis3RenderingStrategy {
+
+    @Override
+    public String getFormattedJdbcPlaceholder(BindableColumn<?> column, String prefix, String parameterName) {
+        String newPrefix = SpringBatchUtility.PARAMETER_KEY + "." + prefix; //$NON-NLS-1$
+        return super.getFormattedJdbcPlaceholder(column, newPrefix, parameterName);
+    }
+}

src/main/java/org/mybatis/dynamic/sql/util/springbatch/SpringBatchUtility.java

@@ -0,0 +1,65 @@
+/**
+ *    Copyright 2016-2019 the original author or authors.
+ *
+ *    Licensed 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.mybatis.dynamic.sql.util.springbatch;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.mybatis.dynamic.sql.BasicColumn;
+import org.mybatis.dynamic.sql.render.RenderingStrategy;
+import org.mybatis.dynamic.sql.select.QueryExpressionDSL;
+import org.mybatis.dynamic.sql.select.SelectDSL;
+import org.mybatis.dynamic.sql.select.render.SelectStatementProvider;
+
+public class SpringBatchUtility {
+    private SpringBatchUtility() {}
+
+    public static final String PARAMETER_KEY = "mybatis3_dsql_query"; //$NON-NLS-1$
+
+    public static final RenderingStrategy SPRING_BATCH_READER_RENDERING_STRATEGY =
+            new SpringBatchReaderRenderingStrategy();
+
+    public static Map<String, Object> toParameterValues(SelectStatementProvider selectStatement) {
+        Map<String, Object> parameterValues = new HashMap<>();
+        parameterValues.put(PARAMETER_KEY, selectStatement);
+        return parameterValues;
+    }
+
+    /**
+     * Select builder that renders in a manner appropriate for the MyBatisPagingItemReader.
+     * 
+     * <b>Important</b> rendered SQL will contain LIMIT and OFFSET clauses in the SELECT statement. If your database
+     * (Oracle) does not support LIMIT and OFFSET, the queries will fail.
+     * 
+     * @param selectList a column list for the SELECT statement
+     * @return FromGatherer used to continue a SELECT statement
+     */
+    public static QueryExpressionDSL.FromGatherer<SpringBatchPagingReaderSelectModel> selectForPaging(
+            BasicColumn...selectList) {
+        return SelectDSL.select(SpringBatchPagingReaderSelectModel::new, selectList);
+    }
+
+    /**
+     * Select builder that renders in a manner appropriate for the MyBatisCursorItemReader.
+     * 
+     * @param selectList a column list for the SELECT statement
+     * @return FromGatherer used to continue a SELECT statement
+     */
+    public static QueryExpressionDSL.FromGatherer<SpringBatchCursorReaderSelectModel> selectForCursor(
+            BasicColumn...selectList) {
+        return SelectDSL.select(SpringBatchCursorReaderSelectModel::new, selectList);
+    }
+}