DRILL-3987: (MOVE) Move logical expressions and operators out of common. Move to new drill-logical model.

1 files changed, 83 insertions, 0 deletions

diff --git a/logical/src/main/java/org/apache/drill/common/expression/FunctionHolderExpression.java b/logical/src/main/java/org/apache/drill/common/expression/FunctionHolderExpression.java
new file mode 100644
index 000000000..d5497f717
--- /dev/null
+++ b/logical/src/main/java/org/apache/drill/common/expression/FunctionHolderExpression.java
@@ -0,0 +1,83 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.drill.common.expression;
+
+import java.util.List;
+
+import org.apache.drill.common.expression.fn.FuncHolder;
+import org.apache.drill.common.expression.visitors.ExprVisitor;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Lists;
+
+public abstract class FunctionHolderExpression extends LogicalExpressionBase {
+  public final ImmutableList<LogicalExpression> args;
+  public final String nameUsed;
+
+  public FunctionHolderExpression(String nameUsed, ExpressionPosition pos, List<LogicalExpression> args) {
+    super(pos);
+    if (args == null) {
+      args = Lists.newArrayList();
+    }
+
+    if (!(args instanceof ImmutableList)) {
+      args = ImmutableList.copyOf(args);
+    }
+    this.args = (ImmutableList<LogicalExpression>) args;
+    this.nameUsed = nameUsed;
+  }
+
+  @Override
+  public <T, V, E extends Exception> T accept(ExprVisitor<T, V, E> visitor, V value) throws E {
+    return visitor.visitFunctionHolderExpression(this, value);
+  }
+
+  /**
+   * A function can have multiple names, it returns the function name used in the query
+   * @return
+   */
+  public String getName() {
+    return nameUsed;
+  }
+
+  /**
+   * constant input expected for i'th argument?
+   * @param i
+   * @return
+   */
+  public abstract boolean argConstantOnly(int i);
+
+  /**
+   * @return aggregating function or not
+   */
+  public abstract boolean isAggregating();
+
+  /**
+   * is the function output non-deterministic?
+   */
+  public abstract boolean isRandom();
+
+  /**
+   * @ return a copy of FunctionHolderExpression, with passed in argument list.
+   */
+  public abstract FunctionHolderExpression copy(List<LogicalExpression> args);
+
+  /** Return the underlying function implementation holder. */
+  public abstract FuncHolder getHolder();
+
+}