Implementing the ability to use add, substract, multiply and divide by a number for the set clause of update query

Author: teillet29200

src/main/java/org/mybatis/dynamic/sql/update/UpdateDSL.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2017 the original author or authors.
+ *    Copyright 2016-2018 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.
@@ -27,6 +27,8 @@
 import org.mybatis.dynamic.sql.SqlTable;
 import org.mybatis.dynamic.sql.VisitableCondition;
 import org.mybatis.dynamic.sql.update.render.UpdateStatementProvider;
+import org.mybatis.dynamic.sql.util.ArithmeticConstantMapping;
+import org.mybatis.dynamic.sql.util.ArithmeticOperation;
 import org.mybatis.dynamic.sql.util.ConstantMapping;
 import org.mybatis.dynamic.sql.util.NullMapping;
 import org.mybatis.dynamic.sql.util.StringConstantMapping;
@@ -126,6 +128,42 @@ public UpdateDSL<R> equalToWhenPresent(Supplier<T> valueSupplier) {
             }
             return UpdateDSL.this;
         }
+        
+        public UpdateDSL<R> incrementBy(T value) {
+            return incrementBy(() -> value);
+        }
+        
+        public UpdateDSL<R> incrementBy(Supplier<T> valueSupplier) {
+            columnsAndValues.add(ArithmeticConstantMapping.of(column, ArithmeticOperation.add, valueSupplier));
+            return UpdateDSL.this;
+        }
+        
+        public UpdateDSL<R> decrementBy(T value) {
+            return decrementBy(() -> value);
+        }
+        
+        public UpdateDSL<R> decrementBy(Supplier<T> valueSupplier) {
+            columnsAndValues.add(ArithmeticConstantMapping.of(column, ArithmeticOperation.substract, valueSupplier));
+            return UpdateDSL.this;
+        }
+        
+        public UpdateDSL<R> multiplyBy(T value) {
+            return multiplyBy(() -> value);
+        }
+        
+        public UpdateDSL<R> multiplyBy(Supplier<T> valueSupplier) {
+            columnsAndValues.add(ArithmeticConstantMapping.of(column, ArithmeticOperation.multiply, valueSupplier));
+            return UpdateDSL.this;
+        }
+        
+        public UpdateDSL<R> divideBy(T value) {
+            return divideBy(() -> value);
+        }
+        
+        public UpdateDSL<R> divideBy(Supplier<T> valueSupplier) {
+            columnsAndValues.add(ArithmeticConstantMapping.of(column, ArithmeticOperation.divide, valueSupplier));
+            return UpdateDSL.this;
+        }
     }
 
     public class UpdateWhereBuilder extends AbstractWhereDSL<UpdateWhereBuilder> {

src/main/java/org/mybatis/dynamic/sql/update/render/SetPhraseVisitor.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2017 the original author or authors.
+ *    Copyright 2016-2018 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.
@@ -20,6 +20,7 @@
 
 import org.mybatis.dynamic.sql.SqlColumn;
 import org.mybatis.dynamic.sql.render.RenderingStrategy;
+import org.mybatis.dynamic.sql.util.ArithmeticConstantMapping;
 import org.mybatis.dynamic.sql.util.ConstantMapping;
 import org.mybatis.dynamic.sql.util.FragmentAndParameters;
 import org.mybatis.dynamic.sql.util.NullMapping;
@@ -78,4 +79,11 @@ private Function<SqlColumn<?>, String> toJdbcPlaceholder(String parameterName) {
         return column -> renderingStrategy
                 .getFormattedJdbcPlaceholder(column, "parameters", parameterName); //$NON-NLS-1$
     }
+
+    @Override
+    public <S> FragmentAndParameters visit(ArithmeticConstantMapping<S> mapping) {
+        String fragment = mapping.mapColumn(SqlColumn::name) + " = " + mapping.mapColumn(SqlColumn::name) + " " + mapping.operation().getOperator() + " " + mapping.valueSupplier().get(); //$NON-NLS-1$
+        return FragmentAndParameters.withFragment(fragment)
+                .build();
+    }
 }

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

@@ -0,0 +1,49 @@
+/**
+ *    Copyright 2016-2018 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;
+
+import java.util.function.Supplier;
+
+import org.mybatis.dynamic.sql.SqlColumn;
+
+public class ArithmeticConstantMapping<T> extends AbstractColumnMapping implements UpdateMapping {
+    private Supplier<T> valueSupplier;
+    private ArithmeticOperation operation;
+
+    private ArithmeticConstantMapping(SqlColumn<?> column, ArithmeticOperation operation, Supplier<T> valueSupplier) {
+        super(column);
+        this.operation = operation;
+        this.valueSupplier = valueSupplier;
+    }
+
+    public Supplier<T> valueSupplier() {
+        return valueSupplier;
+    }
+    
+    public ArithmeticOperation operation() {
+        return operation;
+    }
+
+    public static <T> ArithmeticConstantMapping<T> of(SqlColumn<?> column, ArithmeticOperation operation, Supplier<T> valueSupplier) {
+        ArithmeticConstantMapping<T> mapping = new ArithmeticConstantMapping<>(column, operation, valueSupplier);
+        return mapping;
+    }
+
+    @Override
+    public <R> R accept(UpdateMappingVisitor<R> visitor) {
+        return visitor.visit(this);
+    }
+}

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

@@ -0,0 +1,33 @@
+/**
+ *    Copyright 2016-2018 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;
+
+public enum ArithmeticOperation {
+    add("+"),
+    substract("-"),
+    multiply("*"),
+    divide("/");
+    
+    private String operator;
+    
+    private ArithmeticOperation(String operator) {
+        this.operator = operator;
+    }
+    
+    public String getOperator() {
+        return operator;
+    }
+}

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

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2017 the original author or authors.
+ *    Copyright 2016-2018 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.
@@ -23,4 +23,6 @@ public interface UpdateMappingVisitor<T> {
     T visit(StringConstantMapping mapping);
 
     <S> T visit(ValueMapping<S> mapping);
+    
+    <S> T visit(ArithmeticConstantMapping<S> mapping);
 }

src/test/java/org/mybatis/dynamic/sql/update/UpdateStatementTest.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2016-2017 the original author or authors.
+ *    Copyright 2016-2018 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.
@@ -170,4 +170,28 @@ public void testFullUpdateStatementNoWhere() {
             softly.assertThat(updateStatement.getParameters().get("up2")).isEqualTo("jones");
         });
     }
+    
+    @Test
+    public void testUpdateStatementArithmeticOperation() {
+        UpdateStatementProvider updateStatement = update(foo)
+                .set(id).incrementBy(1)
+                .set(id).decrementBy(2)
+                .set(id).multiplyBy(3)
+                .set(id).divideBy(4)
+                .build()
+                .render(RenderingStrategy.MYBATIS3);
+        
+        String expectedStatement = "update foo " 
+                + "set id = id + 1, "
+                + "id = id - 2, "
+                + "id = id * 3, "
+                + "id = id / 4";
+                
+        SoftAssertions.assertSoftly(softly -> {
+            softly.assertThat(updateStatement.getUpdateStatement()).isEqualTo(expectedStatement);
+        
+            softly.assertThat(updateStatement.getParameters().size()).isEqualTo(0);
+        });
+    }
 }
+