Merge pull request #830 from jeffgbutler/case-in-order-by

Support CASE Expressions in ORDER BY Phrases

Author: jeffgbutler

CHANGELOG.md

@@ -8,6 +8,7 @@ Significant changes:
 
 - The library now requires Java 17
 - Deprecated code from prior releases is removed
+- Allow CASE expressions in ORDER BY Clauses
 
 ## Release 1.5.2 - June 3, 2024
 

pom.xml

@@ -164,14 +164,6 @@
       <version>1.5.6</version>
       <scope>test</scope>
     </dependency>
-    <!-- Hamcrest is only here to make Infinitest happy. Not really used in the project. -->
-    <dependency>
-      <groupId>org.hamcrest</groupId>
-      <artifactId>hamcrest</artifactId>
-      <version>3.0</version>
-      <scope>test</scope>
-    </dependency>
-
     <dependency>
       <groupId>org.testcontainers</groupId>
       <artifactId>postgresql</artifactId>

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

@@ -51,7 +51,7 @@ private <R> Collection<R> applyMapper(Function<? super T, ? extends R> mapper) {
 
     private Collection<T> applyFilter(Predicate<? super T> predicate) {
         Objects.requireNonNull(predicate);
-        return values.stream().filter(predicate).collect(Collectors.toList());
+        return values.stream().filter(predicate).toList();
     }
 
     protected <S extends AbstractListValueCondition<T>> S filterSupport(Predicate<? super T> predicate,

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

@@ -15,6 +15,11 @@
  */
 package org.mybatis.dynamic.sql;
 
+import org.mybatis.dynamic.sql.exception.DynamicSqlException;
+import org.mybatis.dynamic.sql.render.RenderingContext;
+import org.mybatis.dynamic.sql.util.FragmentAndParameters;
+import org.mybatis.dynamic.sql.util.Messages;
+
 /**
  * Defines attributes of columns that are necessary for rendering an order by expression.
  *
@@ -34,13 +39,33 @@ public interface SortSpecification {
      * NOT include the "DESC" word for descending sort specifications.
      *
      * @return the order by phrase
+     * @deprecated Please replace this method by overriding the more general "renderForOrderBy" method. Target for
+     *     removal in release 2.1
      */
-    String orderByName();
+    @Deprecated(since = "2.0", forRemoval = true)
+    default String orderByName() {
+        throw new DynamicSqlException(Messages.getString("ERROR.44")); //$NON-NLS-1$
+    }
 
     /**
      * Return true if the sort order is descending.
      *
      * @return true if the SortSpecification should render as descending
+     * @deprecated Please replace this method by overriding the more general "renderForOrderBy" method. Target for
+     *     removal in release 2.1
      */
-    boolean isDescending();
+    @Deprecated(since = "2.0", forRemoval = true)
+    default boolean isDescending() {
+        throw new DynamicSqlException(Messages.getString("ERROR.44")); //$NON-NLS-1$
+    }
+
+    // the default implementation ensures compatibility with prior releases. When the
+    // deprecated methods are removed, this function can become purely abstract.
+    default FragmentAndParameters renderForOrderBy(RenderingContext renderingContext) {
+        String phrase = orderByName();
+        if (isDescending()) {
+            phrase = phrase + " DESC"; //$NON-NLS-1$
+        }
+        return FragmentAndParameters.fromFragment(phrase);
+    }
 }

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

@@ -30,7 +30,7 @@ public class SqlColumn<T> implements BindableColumn<T>, SortSpecification {
     protected final String name;
     protected final SqlTable table;
     protected final JDBCType jdbcType;
-    protected final boolean isDescending;
+    protected final String descendingPhrase;
     protected final String alias;
     protected final String typeHandler;
     protected final RenderingStrategy renderingStrategy;
@@ -42,7 +42,7 @@ private SqlColumn(Builder<T> builder) {
         name = Objects.requireNonNull(builder.name);
         table = Objects.requireNonNull(builder.table);
         jdbcType = builder.jdbcType;
-        isDescending = builder.isDescending;
+        descendingPhrase = builder.descendingPhrase;
         alias = builder.alias;
         typeHandler = builder.typeHandler;
         renderingStrategy = builder.renderingStrategy;
@@ -87,7 +87,7 @@ public Object convertParameterType(T value) {
     @Override
     public SortSpecification descending() {
         Builder<T> b = copy();
-        return b.withDescending(true).build();
+        return b.withDescendingPhrase(" DESC").build(); //$NON-NLS-1$
     }
 
     @Override
@@ -126,13 +126,8 @@ public SqlColumn<T> asCamelCase() {
     }
 
     @Override
-    public boolean isDescending() {
-        return isDescending;
-    }
-
-    @Override
-    public String orderByName() {
-        return alias().orElse(name);
+    public FragmentAndParameters renderForOrderBy(RenderingContext renderingContext) {
+        return FragmentAndParameters.fromFragment(alias().orElse(name) + descendingPhrase);
     }
 
     @Override
@@ -188,7 +183,7 @@ private <S> Builder<S> copy() {
                 .withName(this.name)
                 .withTable(this.table)
                 .withJdbcType(this.jdbcType)
-                .withDescending(this.isDescending)
+                .withDescendingPhrase(this.descendingPhrase)
                 .withAlias(this.alias)
                 .withTypeHandler(this.typeHandler)
                 .withRenderingStrategy(this.renderingStrategy)
@@ -214,7 +209,7 @@ public static class Builder<T> {
         protected String name;
         protected SqlTable table;
         protected JDBCType jdbcType;
-        protected boolean isDescending = false;
+        protected String descendingPhrase = ""; //$NON-NLS-1$
         protected String alias;
         protected String typeHandler;
         protected RenderingStrategy renderingStrategy;
@@ -237,8 +232,8 @@ public Builder<T> withJdbcType(JDBCType jdbcType) {
             return this;
         }
 
-        public Builder<T> withDescending(boolean isDescending) {
-            this.isDescending = isDescending;
+        public Builder<T> withDescendingPhrase(String descendingPhrase) {
+            this.descendingPhrase = descendingPhrase;
             return this;
         }
 

src/main/java/org/mybatis/dynamic/sql/common/OrderByRenderer.java

@@ -15,24 +15,24 @@
  */
 package org.mybatis.dynamic.sql.common;
 
+import java.util.Objects;
 import java.util.stream.Collectors;
 
-import org.mybatis.dynamic.sql.SortSpecification;
+import org.mybatis.dynamic.sql.render.RenderingContext;
 import org.mybatis.dynamic.sql.util.FragmentAndParameters;
+import org.mybatis.dynamic.sql.util.FragmentCollector;
 
 public class OrderByRenderer {
-    public FragmentAndParameters render(OrderByModel orderByModel) {
-        String phrase = orderByModel.columns()
-                .map(this::calculateOrderByPhrase)
-                .collect(Collectors.joining(", ", "order by ", "")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
-        return FragmentAndParameters.fromFragment(phrase);
+    private final RenderingContext renderingContext;
+
+    public OrderByRenderer(RenderingContext renderingContext) {
+        this.renderingContext = Objects.requireNonNull(renderingContext);
     }
 
-    private String calculateOrderByPhrase(SortSpecification column) {
-        String phrase = column.orderByName();
-        if (column.isDescending()) {
-            phrase = phrase + " DESC"; //$NON-NLS-1$
-        }
-        return phrase;
+    public FragmentAndParameters render(OrderByModel orderByModel) {
+        return orderByModel.columns().map(c -> c.renderForOrderBy(renderingContext))
+                .collect(FragmentCollector.collect())
+                .toFragmentAndParameters(
+                        Collectors.joining(", ", "order by ", "")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
     }
 }

src/main/java/org/mybatis/dynamic/sql/delete/render/DeleteRenderer.java

@@ -96,7 +96,7 @@ private Optional<FragmentAndParameters> calculateOrderByClause() {
     }
 
     private FragmentAndParameters renderOrderByClause(OrderByModel orderByModel) {
-        return new OrderByRenderer().render(orderByModel);
+        return new OrderByRenderer(renderingContext).render(orderByModel);
     }
 
     public static Builder withDeleteModel(DeleteModel deleteModel) {

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

@@ -58,11 +58,11 @@ public BatchInsertModel<T> build() {
     }
 
     @SafeVarargs
-    public static <T> IntoGatherer<T> insert(T... records) {
-        return BatchInsertDSL.insert(Arrays.asList(records));
+    public static <T> BatchInsertDSL.IntoGatherer<T> insert(T... records) {
+        return insert(Arrays.asList(records));
     }
 
-    public static <T> IntoGatherer<T> insert(Collection<T> records) {
+    public static <T> BatchInsertDSL.IntoGatherer<T> insert(Collection<T> records) {
         return new IntoGatherer<>(records);
     }
 

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

@@ -57,11 +57,11 @@ public MultiRowInsertModel<T> build() {
     }
 
     @SafeVarargs
-    public static <T> IntoGatherer<T> insert(T... records) {
-        return MultiRowInsertDSL.insert(Arrays.asList(records));
+    public static <T> MultiRowInsertDSL.IntoGatherer<T> insert(T... records) {
+        return insert(Arrays.asList(records));
     }
 
-    public static <T> IntoGatherer<T> insert(Collection<T> records) {
+    public static <T> MultiRowInsertDSL.IntoGatherer<T> insert(Collection<T> records) {
         return new IntoGatherer<>(records);
     }
 

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

@@ -19,7 +19,6 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
-import java.util.stream.Collectors;
 
 public class BatchInsert<T> {
     private final String insertStatement;
@@ -38,7 +37,7 @@ private BatchInsert(Builder<T> builder) {
     public List<InsertStatementProvider<T>> insertStatements() {
         return records.stream()
                 .map(this::toInsertStatement)
-                .collect(Collectors.toList());
+                .toList();
     }
 
     private InsertStatementProvider<T> toInsertStatement(T row) {
@@ -57,7 +56,7 @@ public String getInsertStatementSQL() {
     }
 
     public List<T> getRecords() {
-        return Collections.unmodifiableList(records);
+        return records;
     }
 
     public static <T> Builder<T> withRecords(List<T> records) {