| /* |
| * 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.phoenix.expression; |
| |
| import java.io.DataInput; |
| import java.io.DataOutput; |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import org.apache.hadoop.io.WritableUtils; |
| |
| import com.google.common.collect.ImmutableList; |
| |
| |
| public abstract class BaseCompoundExpression extends BaseExpression { |
| protected List<Expression> children; |
| private boolean isNullable; |
| private boolean isStateless; |
| private Determinism determinism; |
| private boolean requiresFinalEvaluation; |
| private boolean cloneExpression; |
| |
| public BaseCompoundExpression() { |
| init(Collections.<Expression>emptyList()); |
| } |
| |
| public BaseCompoundExpression(List<Expression> children) { |
| init(children); |
| } |
| |
| private void init(List<Expression> children) { |
| this.children = ImmutableList.copyOf(children); |
| boolean isStateless = true; |
| boolean isNullable = false; |
| boolean requiresFinalEvaluation = false; |
| boolean cloneExpression = false; |
| this.determinism = Determinism.ALWAYS; |
| for (int i = 0; i < children.size(); i++) { |
| Expression child = children.get(i); |
| isNullable |= child.isNullable(); |
| isStateless &= child.isStateless(); |
| this.determinism = this.determinism.combine(child.getDeterminism()); |
| requiresFinalEvaluation |= child.requiresFinalEvaluation(); |
| cloneExpression |= child.isCloneExpression(); |
| } |
| this.isStateless = isStateless; |
| this.isNullable = isNullable; |
| this.requiresFinalEvaluation = requiresFinalEvaluation; |
| this.cloneExpression = cloneExpression; |
| } |
| |
| @Override |
| public List<Expression> getChildren() { |
| return children; |
| } |
| |
| |
| @Override |
| public Determinism getDeterminism() { |
| return determinism; |
| } |
| |
| @Override |
| public boolean isCloneExpression() { |
| return this.cloneExpression; |
| } |
| |
| @Override |
| public boolean isStateless() { |
| return isStateless; |
| } |
| |
| @Override |
| public boolean isNullable() { |
| return isNullable; |
| } |
| |
| @Override |
| public int hashCode() { |
| final int prime = 31; |
| int result = 1; |
| result = prime * result + children.hashCode(); |
| return result; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (this == obj) return true; |
| if (obj == null) return false; |
| if (getClass() != obj.getClass()) return false; |
| BaseCompoundExpression other = (BaseCompoundExpression)obj; |
| if (!children.equals(other.children)) return false; |
| return true; |
| } |
| |
| @Override |
| public void readFields(DataInput input) throws IOException { |
| int len = WritableUtils.readVInt(input); |
| List<Expression>children = new ArrayList<Expression>(len); |
| for (int i = 0; i < len; i++) { |
| Expression child = ExpressionType.values()[WritableUtils.readVInt(input)].newInstance(); |
| child.readFields(input); |
| children.add(child); |
| } |
| init(children); |
| } |
| |
| @Override |
| public void write(DataOutput output) throws IOException { |
| WritableUtils.writeVInt(output, children.size()); |
| for (int i = 0; i < children.size(); i++) { |
| Expression child = children.get(i); |
| WritableUtils.writeVInt(output, ExpressionType.valueOf(child).ordinal()); |
| child.write(output); |
| } |
| } |
| |
| @Override |
| public void reset() { |
| for (int i = 0; i < children.size(); i++) { |
| children.get(i).reset(); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return this.getClass().getName() + " [children=" + children + "]"; |
| } |
| |
| @Override |
| public boolean requiresFinalEvaluation() { |
| return requiresFinalEvaluation; |
| } |
| } |