#1633 - ENH: Add bind parameter expansion for raw() expressions

src/main/java/io/ebeaninternal/server/expression/DefaultExpressionFactory.java

@@ -529,7 +529,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
    */
   @Override
   public Expression raw(String raw, Object value) {
-    return new RawExpression(raw, new Object[]{value});
+    return RawExpressionBuilder.buildSingle(raw, value);
   }
 
   /**
@@ -541,7 +541,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
    */
   @Override
   public Expression raw(String raw, Object[] values) {
-    return new RawExpression(raw, values);
+    return RawExpressionBuilder.build(raw, values);
   }
 
   /**

src/main/java/io/ebeaninternal/server/expression/RawExpression.java

@@ -12,9 +12,9 @@ import java.util.Collection;
 
 class RawExpression extends NonPrepareExpression {
 
-  private final String sql;
+  final String sql;
 
-  private final Object[] values;
+  final Object[] values;
 
   RawExpression(String sql, Object[] values) {
     this.sql = sql;

src/main/java/io/ebeaninternal/server/expression/RawExpressionBuilder.java

@@ -0,0 +1,86 @@
+package io.ebeaninternal.server.expression;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+class RawExpressionBuilder {
+
+  private static final String BP_1 = "?1";
+
+  private static final String[] BP = {BP_1, "?2", "?3", "?4", "?5", "?6", "?7", "?8",
+    "?9", "?10", "?11", "?12", "?13", "?14", "?15", "?16", "?17", "?18", "?19", "?20"};
+
+  /**
+   * Build RawExpression taking into account parameter expansion.
+   */
+  static RawExpression buildSingle(String raw, Object value) {
+    if (isExpand(value, raw, BP_1)) {
+      Collection val = (Collection) value;
+      raw = raw.replace(BP_1, expand(val));
+      return new RawExpression(raw, val.toArray());
+    }
+    return new RawExpression(raw, new Object[]{value});
+  }
+
+  /**
+   * Build RawExpression for multiple bind values taking into account parameter expansion.
+   */
+  static RawExpression build(String raw, Object[] values) {
+
+    for (int i = 0; i < values.length; i++) {
+      if (isExpand(values[i], raw, match(i))) {
+        return new RawExpressionBuilder(raw, values).build();
+      }
+    }
+    return new RawExpression(raw, values);
+  }
+
+  /**
+   * Return true if this value is a collection that should be expanded.
+   */
+  private static boolean isExpand(Object value, String raw, String bindMatch) {
+    return value instanceof Collection && raw.contains(bindMatch);
+  }
+
+  private static String match(int i) {
+    if (i < 20) {
+      return BP[i];
+    }
+    return "?" + (i + 1);
+  }
+
+  private static String expand(Collection values) {
+
+    StringBuilder sqlExpand = new StringBuilder(values.size() * 2);
+    for (int i = 0; i < values.size(); i++) {
+      if (i > 0) {
+        sqlExpand.append(",");
+      }
+      sqlExpand.append("?");
+    }
+    return sqlExpand.toString();
+  }
+
+  private final String expanded;
+
+  private final List<Object> params = new ArrayList<>();
+
+  private RawExpressionBuilder(String raw, Object[] values) {
+    for (int i = 0; i < values.length; i++) {
+      String match = match(i);
+      if (!isExpand(values[i], raw, match)) {
+        params.add(values[i]);
+      } else {
+        Collection val = (Collection) values[i];
+        params.addAll(val);
+        raw = raw.replace(match, expand(val));
+      }
+    }
+    this.expanded = raw;
+  }
+
+  private RawExpression build() {
+    return new RawExpression(expanded, params.toArray());
+  }
+}