Merge pull request #218 from jeffgbutler/delay-when-present-calculations

Delay "when present" Calculations on Inserts and Updates

Author: jeffgbutler

src/main/java/org/mybatis/dynamic/sql/insert/GeneralInsertDSL.java

@@ -27,6 +27,7 @@
 import org.mybatis.dynamic.sql.util.NullMapping;
 import org.mybatis.dynamic.sql.util.StringConstantMapping;
 import org.mybatis.dynamic.sql.util.ValueMapping;
+import org.mybatis.dynamic.sql.util.ValueWhenPresentMapping;
 
 public class GeneralInsertDSL {
     private List<AbstractColumnMapping> insertMappings = new ArrayList<>();
@@ -88,9 +89,7 @@ public GeneralInsertDSL toValueWhenPresent(T value) {
         }
 
         public GeneralInsertDSL toValueWhenPresent(Supplier<T> valueSupplier) {
-            if (valueSupplier.get() != null) {
-                insertMappings.add(ValueMapping.of(column, valueSupplier));
-            }
+            insertMappings.add(ValueWhenPresentMapping.of(column, valueSupplier));
             return GeneralInsertDSL.this;
         }
     }

src/main/java/org/mybatis/dynamic/sql/insert/InsertDSL.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2019 the original author or authors.
+ *    Copyright 2016-2020 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.
@@ -25,6 +25,7 @@
 import org.mybatis.dynamic.sql.util.ConstantMapping;
 import org.mybatis.dynamic.sql.util.NullMapping;
 import org.mybatis.dynamic.sql.util.PropertyMapping;
+import org.mybatis.dynamic.sql.util.PropertyWhenPresentMapping;
 import org.mybatis.dynamic.sql.util.StringConstantMapping;
 
 public class InsertDSL<T> {
@@ -78,9 +79,7 @@ public InsertDSL<T> toProperty(String property) {
         }
 
         public InsertDSL<T> toPropertyWhenPresent(String property, Supplier<?> valueSupplier) {
-            if (valueSupplier.get() != null) {
-                toProperty(property);
-            }
+            columnMappings.add(PropertyWhenPresentMapping.of(column, property, valueSupplier));
             return InsertDSL.this;
         }
 

src/main/java/org/mybatis/dynamic/sql/insert/render/BatchInsertRenderer.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2019 the original author or authors.
+ *    Copyright 2016-2020 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.
@@ -17,7 +17,9 @@
 
 import static org.mybatis.dynamic.sql.util.StringUtilities.spaceBefore;
 
+import java.util.List;
 import java.util.Objects;
+import java.util.stream.Collectors;
 
 import org.mybatis.dynamic.sql.insert.BatchInsertModel;
 import org.mybatis.dynamic.sql.render.RenderingStrategy;
@@ -33,22 +35,28 @@ private BatchInsertRenderer(Builder<T> builder) {
     }
 
     public BatchInsert<T> render() {
-        ValuePhraseVisitor visitor = new ValuePhraseVisitor(renderingStrategy);
-        FieldAndValueCollector collector = model.mapColumnMappings(MultiRowRenderingUtilities.toFieldAndValue(visitor))
-                .collect(FieldAndValueCollector.collect());
+        MultiRowValuePhraseVisitor visitor = new MultiRowValuePhraseVisitor(renderingStrategy, "record"); //$NON-NLS-1$)
+        List<FieldAndValue> fieldsAndValues = model.mapColumnMappings(MultiRowRenderingUtilities.toFieldAndValue(visitor))
+                .collect(Collectors.toList());
 
         return BatchInsert.withRecords(model.records())
-                .withInsertStatement(calculateInsertStatement(collector))
+                .withInsertStatement(calculateInsertStatement(fieldsAndValues))
                 .build();
     }
 
-    private String calculateInsertStatement(FieldAndValueCollector collector) {
+    private String calculateInsertStatement(List<FieldAndValue> fieldsAndValues) {
         return "insert into" //$NON-NLS-1$
                 + spaceBefore(model.table().tableNameAtRuntime())
-                + spaceBefore(collector.columnsPhrase())
-                + spaceBefore(collector.valuesPhrase());
+                + spaceBefore(MultiRowRenderingUtilities.calculateColumnsPhrase(fieldsAndValues))
+                + spaceBefore(calculateVluesPhrase(fieldsAndValues));
     }
 
+    private String calculateVluesPhrase(List<FieldAndValue> fieldsAndValues) {
+        return fieldsAndValues.stream()
+                .map(FieldAndValue::valuePhrase)
+                .collect(Collectors.joining(", ", "values (", ")")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
+    }
+
     public static <T> Builder<T> withBatchInsertModel(BatchInsertModel<T> model) {
         return new Builder<T>().withBatchInsertModel(model);
     }

src/main/java/org/mybatis/dynamic/sql/insert/render/FieldAndValue.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2019 the original author or authors.
+ *    Copyright 2016-2020 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.
@@ -16,6 +16,7 @@
 package org.mybatis.dynamic.sql.insert.render;
 
 import java.util.Objects;
+import java.util.Optional;
 
 public class FieldAndValue {
     private String fieldName;
@@ -59,5 +60,9 @@ public Builder withValuePhrase(String valuePhrase) {
         public FieldAndValue build() {
             return new FieldAndValue(this);
         }
+        
+        public Optional<FieldAndValue> buildOptional() {
+            return Optional.of(build());
+        }
     }
 }

src/main/java/org/mybatis/dynamic/sql/insert/render/FieldAndValueAndParameters.java

@@ -18,6 +18,7 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Optional;
 
 public class FieldAndValueAndParameters {
     private String fieldName;
@@ -69,5 +70,9 @@ public Builder withParameter(String key, Object value) {
         public FieldAndValueAndParameters build() {
             return new FieldAndValueAndParameters(this);
         }
+        
+        public Optional<FieldAndValueAndParameters> buildOptional() {
+            return Optional.of(build());
+        }
     }
 }

src/main/java/org/mybatis/dynamic/sql/insert/render/FieldAndValueAndParametersCollector.java

@@ -17,8 +17,13 @@
 
 import static org.mybatis.dynamic.sql.util.StringUtilities.spaceBefore;
 
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Function;
+import java.util.stream.Collectors;
 
 import org.mybatis.dynamic.sql.insert.GeneralInsertModel;
 import org.mybatis.dynamic.sql.render.RenderingStrategy;
@@ -36,31 +41,55 @@ private GeneralInsertRenderer(Builder builder) {
 
     public GeneralInsertStatementProvider render() {
         GeneralInsertValuePhraseVisitor visitor = new GeneralInsertValuePhraseVisitor(renderingStrategy);
-        FieldAndValueAndParametersCollector collector = model.mapColumnMappings(toFieldAndValue(visitor))
-                .collect(FieldAndValueAndParametersCollector.collect());
+        List<Optional<FieldAndValueAndParameters>> fieldsAndValues = model.mapColumnMappings(toFieldAndValue(visitor))
+                .collect(Collectors.toList());
 
-        return DefaultGeneralInsertStatementProvider.withInsertStatement(calculateInsertStatement(collector))
-                .withParameters(collector.parameters())
+        return DefaultGeneralInsertStatementProvider.withInsertStatement(calculateInsertStatement(fieldsAndValues))
+                .withParameters(calculateParameters(fieldsAndValues))
                 .build();
     }
 
-    private String calculateInsertStatement(FieldAndValueAndParametersCollector collector) {
+    private String calculateInsertStatement(List<Optional<FieldAndValueAndParameters>> fieldsAndValues) {
         return "insert into" //$NON-NLS-1$
                 + spaceBefore(model.table().tableNameAtRuntime())
-                + spaceBefore(collector.columnsPhrase())
-                + spaceBefore(collector.valuesPhrase());
+                + spaceBefore(calculateColumnsPhrase(fieldsAndValues))
+                + spaceBefore(calculateValuesPhrase(fieldsAndValues));
     }
 
-    private Function<AbstractColumnMapping, FieldAndValueAndParameters> toFieldAndValue(
+    private Function<AbstractColumnMapping, Optional<FieldAndValueAndParameters>> toFieldAndValue(
             GeneralInsertValuePhraseVisitor visitor) {
         return insertMapping -> toFieldAndValue(visitor, insertMapping);
     }
 
-    private FieldAndValueAndParameters toFieldAndValue(GeneralInsertValuePhraseVisitor visitor,
+    private Optional<FieldAndValueAndParameters> toFieldAndValue(GeneralInsertValuePhraseVisitor visitor,
             AbstractColumnMapping insertMapping) {
         return insertMapping.accept(visitor);
     }
 
+    private String calculateColumnsPhrase(List<Optional<FieldAndValueAndParameters>> fieldsAndValues) {
+        return fieldsAndValues.stream()
+                .filter(Optional::isPresent)
+                .map(Optional::get)
+                .map(FieldAndValueAndParameters::fieldName)
+                .collect(Collectors.joining(", ", "(", ")")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
+    }
+
+    private String calculateValuesPhrase(List<Optional<FieldAndValueAndParameters>> fieldsAndValues) {
+        return fieldsAndValues.stream()
+                .filter(Optional::isPresent)
+                .map(Optional::get)
+                .map(FieldAndValueAndParameters::valuePhrase)
+                .collect(Collectors.joining(", ", "values (", ")")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
+    }
+    
+    private Map<String, Object> calculateParameters(List<Optional<FieldAndValueAndParameters>> fieldsAndValues) {
+        return fieldsAndValues.stream()
+                .filter(Optional::isPresent)
+                .map(Optional::get)
+                .map(FieldAndValueAndParameters::parameters)
+                .collect(HashMap::new, HashMap::putAll, HashMap::putAll);
+    }
+
     public static Builder withInsertModel(GeneralInsertModel model) {
         return new Builder().withInsertModel(model);
     }