Add StdFunctions, StdExpressions, TQColumn marker interface

ebean-querybean/src/main/java/io/ebean/typequery/StdExpressions.java

@@ -0,0 +1,35 @@
+package io.ebean.typequery;
+
+import io.ebean.Expr;
+import io.ebean.Expression;
+
+public class StdExpressions {
+
+  public static Expression gt(TQColumn property, Object value) {
+    return Expr.gt(property.toString(), value);
+  }
+
+  public static Expression like(TQColumn property, String value) {
+    return Expr.like(property.toString(), value);
+  }
+
+  public static Expression ilike(TQColumn property, String value) {
+    return Expr.ilike(property.toString(), value);
+  }
+
+  public static Expression startsWith(TQColumn property, String value) {
+    return Expr.startsWith(property.toString(), value);
+  }
+
+  public static Expression istartsWith(TQColumn property, String value) {
+    return Expr.istartsWith(property.toString(), value);
+  }
+
+  public static Expression contains(TQColumn property, String value) {
+    return Expr.contains(property.toString(), value);
+  }
+
+  public static Expression icontains(TQColumn property, String value) {
+    return Expr.icontains(property.toString(), value);
+  }
+}

ebean-querybean/src/main/java/io/ebean/typequery/StdFunctions.java

@@ -0,0 +1,52 @@
+package io.ebean.typequery;
+
+public final class StdFunctions {
+
+  public static TQColumn max(TQColumn property) {
+    return new Standard("max(" + property + ")");
+  }
+
+  public static TQColumn sum(TQColumn property) {
+    return new Standard("sum(" + property + ")");
+  }
+
+  public static TQColumn concat(TQColumn property, Object... values) {
+    StringBuilder expression = new StringBuilder(50);
+    expression.append("concat(").append(property.toString());
+    for (Object value : values) {
+      expression.append(",").append(sqlStringExpression(value));
+    }
+    expression.append(")");
+    return new Standard(expression.toString());
+  }
+
+  public static TQColumn coalesce(TQColumn property, Object value) {
+    StringBuilder expression = new StringBuilder(50);
+    expression.append("coalesce(").append(property.toString()).append(",");
+    expression.append(sqlStringExpression(value));
+    expression.append(")");
+    return new Standard(expression.toString());
+  }
+
+  private static String sqlStringExpression(Object value) {
+    if (value instanceof TQColumn || value instanceof Number) {
+      return value.toString();
+    } else {
+      return "'" + value + "'";
+    }
+  }
+
+  private static class Standard implements TQColumn {
+
+    private final String expression;
+
+    private Standard(String expression) {
+      this.expression = expression;
+    }
+
+    @Override
+    public String toString() {
+      return expression;
+    }
+  }
+}

ebean-querybean/src/main/java/io/ebean/typequery/TQColumn.java

@@ -0,0 +1,7 @@
+package io.ebean.typequery;
+
+/**
+ * Marker interface for type safe properties and expressions.
+ */
+public interface TQColumn {
+}

ebean-querybean/src/main/java/io/ebean/typequery/TQProperty.java

@@ -7,7 +7,7 @@ import io.ebean.ExpressionList;
  *
  * @param <R> The type of the owning root bean
  */
-public class TQProperty<R> {
+public class TQProperty<R> implements TQColumn {
 
   protected final String _name;
 
@@ -31,6 +31,7 @@ public class TQProperty<R> {
     this._name = TQPath.add(prefix, name);
   }
 
+  @Override
   public String toString() {
     return _name;
   }

ebean-querybean/src/main/java/io/ebean/typequery/TQRootBean.java

@@ -233,8 +233,13 @@ public abstract class TQRootBean<T, R> {
   }
 
   /**
-   * Tune the query by specifying the properties to be loaded on the
-   * 'main' root level entity bean (aka partial object).
+   * Specify the properties to be loaded on the 'main' root level entity bean.
+   * <p>
+   * The resulting entities with be "partially loaded" aka partial objects.
+   * <p>
+   * Alternatively we can use a {@link #select(FetchGroup)} to specify all properties
+   * to load on all parts of the graph.
+   *
    * <pre>{@code
    *
    *   // alias for the customer properties in select()
@@ -245,12 +250,12 @@ public abstract class TQRootBean<T, R> {
    *
    *   List<Customer> customers =
    *     new QCustomer()
-   *       // tune query
+   *       // specify the parts of the graph we want to load
    *       .select(cust.id, cust.name)
    *       .contacts.fetch(contact.firstName, contact.lastName, contact.email)
    *
    *       // predicates
-   *       .id.greaterThan(1)
+   *       .id.gt(1)
    *       .findList();
    *
    * }</pre>
@@ -263,14 +268,25 @@ public abstract class TQRootBean<T, R> {
     return root;
   }
 
-  private Set<String> properties(TQProperty<R>[] properties) {
+  private Set<String> properties(TQColumn[] properties) {
     Set<String> props = new LinkedHashSet<>();
-    for (TQProperty<R> property : properties) {
-      props.add(property.propertyName());
+    for (TQColumn property : properties) {
+      props.add(property.toString());
     }
     return props;
   }
 
+  /**
+   * Specify the properties to be loaded on the 'main' root level entity bean
+   * also allowing for functions to be used like {@link StdFunctions#max(TQColumn)}.
+   *
+   * @param properties the list of properties to fetch
+   */
+  public final R select(TQColumn... properties) {
+    ((SpiQueryFetch) query).selectProperties(properties(properties));
+    return root;
+  }
+
   /**
    * Specify a path to load including all its properties.
    *
@@ -499,6 +515,14 @@ public abstract class TQRootBean<T, R> {
     return root;
   }
 
+  /**
+   * Add an expression to the WHERE or HAVING clause.
+   */
+  public R add(Expression expression) {
+    peekExprList().add(expression);
+    return root;
+  }
+
   /**
    * Set root table alias.
    */