Add filterExpressions as a concept

qqq-backend-core/src/main/java/com/kingsrook/qqq/backend/core/model/actions/tables/query/QFilterCriteria.java

@@ -27,6 +27,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import com.kingsrook.qqq.backend.core.logging.QLogger;
+import com.kingsrook.qqq.backend.core.model.actions.tables.query.expressions.AbstractFilterExpression;
 import com.kingsrook.qqq.backend.core.utils.CollectionUtils;
 import com.kingsrook.qqq.backend.core.utils.StringUtils;
 
@@ -44,6 +45,7 @@ public class QFilterCriteria implements Serializable, Cloneable
    private List<Serializable> values;
 
    private String otherFieldName;
+   private AbstractFilterExpression<?> expression;
 
 
 
@@ -302,4 +304,35 @@ public class QFilterCriteria implements Serializable, Cloneable
 
       return (rs.toString());
    }
+
+   /*******************************************************************************
+    ** Getter for expression
+    *******************************************************************************/
+   public AbstractFilterExpression<?> getExpression()
+   {
+      return (this.expression);
+   }
+
+
+
+   /*******************************************************************************
+    ** Setter for expression
+    *******************************************************************************/
+   public void setExpression(AbstractFilterExpression<?> expression)
+   {
+      this.expression = expression;
+   }
+
+
+
+   /*******************************************************************************
+    ** Fluent setter for expression
+    *******************************************************************************/
+   public QFilterCriteria withExpression(AbstractFilterExpression<?> expression)
+   {
+      this.expression = expression;
+      return (this);
+   }
+
+
 }

qqq-backend-core/src/main/java/com/kingsrook/qqq/backend/core/model/actions/tables/query/expressions/AbstractFilterExpression.java

@@ -0,0 +1,37 @@
+/*
+ * QQQ - Low-code Application Framework for Engineers.
+ * Copyright (C) 2021-2023.  Kingsrook, LLC
+ * 651 N Broad St Ste 205 # 6917 | Middletown DE 19709 | United States
+ * contact@kingsrook.com
+ * https://github.com/Kingsrook/
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.kingsrook.qqq.backend.core.model.actions.tables.query.expressions;
+
+
+import java.io.Serializable;
+
+
+/*******************************************************************************
+ **
+ *******************************************************************************/
+public abstract class AbstractFilterExpression<T extends Serializable>
+{
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   public abstract T evaluate();
+}

qqq-backend-core/src/main/java/com/kingsrook/qqq/backend/core/model/actions/tables/query/expressions/Now.java

@@ -0,0 +1,43 @@
+/*
+ * QQQ - Low-code Application Framework for Engineers.
+ * Copyright (C) 2021-2023.  Kingsrook, LLC
+ * 651 N Broad St Ste 205 # 6917 | Middletown DE 19709 | United States
+ * contact@kingsrook.com
+ * https://github.com/Kingsrook/
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.kingsrook.qqq.backend.core.model.actions.tables.query.expressions;
+
+
+import java.time.Instant;
+
+
+/*******************************************************************************
+ **
+ *******************************************************************************/
+public class Now extends AbstractFilterExpression<Instant>
+{
+
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   @Override
+   public Instant evaluate()
+   {
+      return (Instant.now());
+   }
+
+}

qqq-backend-core/src/main/java/com/kingsrook/qqq/backend/core/model/actions/tables/query/expressions/NowWithOffset.java

@@ -0,0 +1,128 @@
+/*
+ * QQQ - Low-code Application Framework for Engineers.
+ * Copyright (C) 2021-2023.  Kingsrook, LLC
+ * 651 N Broad St Ste 205 # 6917 | Middletown DE 19709 | United States
+ * contact@kingsrook.com
+ * https://github.com/Kingsrook/
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.kingsrook.qqq.backend.core.model.actions.tables.query.expressions;
+
+
+import java.time.Instant;
+import java.util.concurrent.TimeUnit;
+
+
+/*******************************************************************************
+ **
+ *******************************************************************************/
+public class NowWithOffset extends AbstractFilterExpression<Instant>
+{
+   private final Operator operator;
+   private final int      amount;
+   private final TimeUnit timeUnit;
+
+
+
+   public enum Operator
+   {PLUS, MINUS}
+
+
+
+   /*******************************************************************************
+    ** Constructor
+    **
+    *******************************************************************************/
+   private NowWithOffset(Operator operator, int amount, TimeUnit timeUnit)
+   {
+      this.operator = operator;
+      this.amount = amount;
+      this.timeUnit = timeUnit;
+   }
+
+
+
+   /*******************************************************************************
+    ** Factory
+    **
+    *******************************************************************************/
+   public static NowWithOffset minus(int amount, TimeUnit timeUnit)
+   {
+      return (new NowWithOffset(Operator.MINUS, amount, timeUnit));
+   }
+
+
+
+   /*******************************************************************************
+    ** Factory
+    **
+    *******************************************************************************/
+   public static NowWithOffset plus(int amount, TimeUnit timeUnit)
+   {
+      return (new NowWithOffset(Operator.PLUS, amount, timeUnit));
+   }
+
+
+
+   /*******************************************************************************
+    **
+    *******************************************************************************/
+   @Override
+   public Instant evaluate()
+   {
+      if(operator.equals(Operator.PLUS))
+      {
+         return (Instant.now().plus(amount, timeUnit.toChronoUnit()));
+      }
+      else
+      {
+         return (Instant.now().minus(amount, timeUnit.toChronoUnit()));
+      }
+   }
+
+
+
+   /*******************************************************************************
+    ** Getter for operator
+    **
+    *******************************************************************************/
+   public Operator getOperator()
+   {
+      return operator;
+   }
+
+
+
+   /*******************************************************************************
+    ** Getter for amount
+    **
+    *******************************************************************************/
+   public int getAmount()
+   {
+      return amount;
+   }
+
+
+
+   /*******************************************************************************
+    ** Getter for timeUnit
+    **
+    *******************************************************************************/
+   public TimeUnit getTimeUnit()
+   {
+      return timeUnit;
+   }
+}