Refactor column hierarchy so we can build un-typed functions

Author: jeffgbutler

src/main/java/org/mybatis/dynamic/sql/BasicColumn.java

@@ -15,9 +15,11 @@
  */
 package org.mybatis.dynamic.sql;
 
+import java.sql.JDBCType;
 import java.util.Optional;
 
 import org.mybatis.dynamic.sql.render.RenderingContext;
+import org.mybatis.dynamic.sql.render.RenderingStrategy;
 import org.mybatis.dynamic.sql.util.FragmentAndParameters;
 
 /**
@@ -58,6 +60,18 @@ public interface BasicColumn {
      */
     FragmentAndParameters render(RenderingContext renderingContext);
 
+    default Optional<JDBCType> jdbcType() {
+        return Optional.empty();
+    }
+
+    default Optional<String> typeHandler() {
+        return Optional.empty();
+    }
+
+    default Optional<RenderingStrategy> renderingStrategy() {
+        return Optional.empty();
+    }
+
     /**
      * Utility method to make it easier to build column lists for methods that require an
      * array rather than the varargs method.

src/main/java/org/mybatis/dynamic/sql/BindableColumn.java

@@ -15,14 +15,11 @@
  */
 package org.mybatis.dynamic.sql;
 
-import java.sql.JDBCType;
 import java.util.Optional;
 
-import org.mybatis.dynamic.sql.render.RenderingStrategy;
-
 /**
- * Describes additional attributes of columns that are necessary for binding the column as a JDBC parameter.
- * Columns in where clauses are typically bound.
+ * Describes a column with a known data type. The type is only used by the compiler to assure type safety
+ * when building clauses with conditions.
  *
  * @author Jeff Butler
  *
@@ -37,18 +34,6 @@ public interface BindableColumn<T> extends BasicColumn {
     @Override
     BindableColumn<T> as(String alias);
 
-    default Optional<JDBCType> jdbcType() {
-        return Optional.empty();
-    }
-
-    default Optional<String> typeHandler() {
-        return Optional.empty();
-    }
-
-    default Optional<RenderingStrategy> renderingStrategy() {
-        return Optional.empty();
-    }
-
     default Object convertParameterType(T value) {
         return value;
     }

src/main/java/org/mybatis/dynamic/sql/SqlBuilder.java

@@ -497,6 +497,10 @@ static <T> Sum<T> sum(BindableColumn<T> column) {
         return Sum.of(column);
     }
 
+    static Sum<Object> sum(BasicColumn column) {
+        return Sum.of(column);
+    }
+
     static <T> Sum<T> sum(BindableColumn<T> column, VisitableCondition<T> condition) {
         return Sum.of(column, condition);
     }

src/main/java/org/mybatis/dynamic/sql/select/aggregate/Avg.java

@@ -15,14 +15,15 @@
  */
 package org.mybatis.dynamic.sql.select.aggregate;
 
+import org.mybatis.dynamic.sql.BasicColumn;
 import org.mybatis.dynamic.sql.BindableColumn;
 import org.mybatis.dynamic.sql.render.RenderingContext;
 import org.mybatis.dynamic.sql.select.function.AbstractUniTypeFunction;
 import org.mybatis.dynamic.sql.util.FragmentAndParameters;
 
 public class Avg<T> extends AbstractUniTypeFunction<T, Avg<T>> {
 
-    private Avg(BindableColumn<T> column) {
+    private Avg(BasicColumn column) {
         super(column);
     }
 

src/main/java/org/mybatis/dynamic/sql/select/aggregate/Max.java

@@ -15,14 +15,15 @@
  */
 package org.mybatis.dynamic.sql.select.aggregate;
 
+import org.mybatis.dynamic.sql.BasicColumn;
 import org.mybatis.dynamic.sql.BindableColumn;
 import org.mybatis.dynamic.sql.render.RenderingContext;
 import org.mybatis.dynamic.sql.select.function.AbstractUniTypeFunction;
 import org.mybatis.dynamic.sql.util.FragmentAndParameters;
 
 public class Max<T> extends AbstractUniTypeFunction<T, Max<T>> {
 
-    private Max(BindableColumn<T> column) {
+    private Max(BasicColumn column) {
         super(column);
     }
 

src/main/java/org/mybatis/dynamic/sql/select/aggregate/Min.java

@@ -15,14 +15,15 @@
  */
 package org.mybatis.dynamic.sql.select.aggregate;
 
+import org.mybatis.dynamic.sql.BasicColumn;
 import org.mybatis.dynamic.sql.BindableColumn;
 import org.mybatis.dynamic.sql.render.RenderingContext;
 import org.mybatis.dynamic.sql.select.function.AbstractUniTypeFunction;
 import org.mybatis.dynamic.sql.util.FragmentAndParameters;
 
 public class Min<T> extends AbstractUniTypeFunction<T, Min<T>> {
 
-    private Min(BindableColumn<T> column) {
+    private Min(BasicColumn column) {
         super(column);
     }
 

src/main/java/org/mybatis/dynamic/sql/select/aggregate/Sum.java

@@ -17,6 +17,7 @@
 
 import java.util.function.Function;
 
+import org.mybatis.dynamic.sql.BasicColumn;
 import org.mybatis.dynamic.sql.BindableColumn;
 import org.mybatis.dynamic.sql.VisitableCondition;
 import org.mybatis.dynamic.sql.render.RenderingContext;
@@ -28,7 +29,7 @@
 public class Sum<T> extends AbstractUniTypeFunction<T, Sum<T>> {
     private final Function<RenderingContext, FragmentAndParameters> renderer;
 
-    private Sum(BindableColumn<T> column) {
+    private Sum(BasicColumn column) {
         super(column);
         renderer = rc -> column.render(rc).mapFragment(this::applyAggregate);
     }
@@ -48,7 +49,7 @@ private Sum(BindableColumn<T> column, VisitableCondition<T> condition) {
         };
     }
 
-    private Sum(BindableColumn<T> column, Function<RenderingContext, FragmentAndParameters> renderer) {
+    private Sum(BasicColumn column, Function<RenderingContext, FragmentAndParameters> renderer) {
         super(column);
         this.renderer = renderer;
     }
@@ -71,6 +72,10 @@ public static <T> Sum<T> of(BindableColumn<T> column) {
         return new Sum<>(column);
     }
 
+    public static Sum<Object> of(BasicColumn column) {
+        return new Sum<>(column);
+    }
+
     public static <T> Sum<T> of(BindableColumn<T> column, VisitableCondition<T> condition) {
         return new Sum<>(column, condition);
     }

src/main/java/org/mybatis/dynamic/sql/select/function/AbstractTypeConvertingFunction.java

@@ -18,6 +18,7 @@
 import java.util.Objects;
 import java.util.Optional;
 
+import org.mybatis.dynamic.sql.BasicColumn;
 import org.mybatis.dynamic.sql.BindableColumn;
 
 /**
@@ -36,10 +37,10 @@
  */
 public abstract class AbstractTypeConvertingFunction<T, R, U extends AbstractTypeConvertingFunction<T, R, U>>
         implements BindableColumn<R> {
-    protected final BindableColumn<T> column;
+    protected final BasicColumn column;
     protected String alias;
 
-    protected AbstractTypeConvertingFunction(BindableColumn<T> column) {
+    protected AbstractTypeConvertingFunction(BasicColumn column) {
         this.column = Objects.requireNonNull(column);
     }
 

src/main/java/org/mybatis/dynamic/sql/select/function/AbstractUniTypeFunction.java

@@ -18,7 +18,7 @@
 import java.sql.JDBCType;
 import java.util.Optional;
 
-import org.mybatis.dynamic.sql.BindableColumn;
+import org.mybatis.dynamic.sql.BasicColumn;
 
 /**
  * Represents a function that does not change the underlying data type.
@@ -33,7 +33,7 @@
 public abstract class AbstractUniTypeFunction<T, U extends AbstractUniTypeFunction<T, U>>
         extends AbstractTypeConvertingFunction<T, T, U> {
 
-    protected AbstractUniTypeFunction(BindableColumn<T> column) {
+    protected AbstractUniTypeFunction(BasicColumn column) {
         super(column);
     }
 

src/main/java/org/mybatis/dynamic/sql/select/function/Add.java

@@ -23,7 +23,7 @@
 
 public class Add<T> extends OperatorFunction<T> {
 
-    private Add(BindableColumn<T> firstColumn, BasicColumn secondColumn,
+    private Add(BasicColumn firstColumn, BasicColumn secondColumn,
             List<BasicColumn> subsequentColumns) {
         super("+", firstColumn, secondColumn, subsequentColumns); //$NON-NLS-1$
     }