| // 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.impala.catalog; |
| |
| import org.apache.commons.lang3.StringUtils; |
| |
| import org.apache.impala.thrift.TColumnType; |
| import org.apache.impala.thrift.TStructField; |
| import org.apache.impala.thrift.TTypeNode; |
| |
| /** |
| * TODO: Support comments for struct fields. The Metastore does not properly store |
| * comments of struct fields. We set comment_ to null to avoid compatibility issues. |
| */ |
| public class StructField { |
| protected final String name_; |
| protected final Type type_; |
| protected final String comment_; |
| protected int position_; // in struct |
| |
| public StructField(String name, Type type, String comment) { |
| // Impala expects field names to be in lower case, but type strings stored in the HMS |
| // are not guaranteed to be lower case. |
| name_ = name.toLowerCase(); |
| type_ = type; |
| comment_ = comment; |
| } |
| |
| public StructField(String name, Type type) { |
| this(name, type, null); |
| } |
| |
| public String getComment() { return comment_; } |
| public String getName() { return name_; } |
| public Type getType() { return type_; } |
| public int getPosition() { return position_; } |
| public void setPosition(int position) { position_ = position; } |
| |
| public String toSql(int depth) { |
| String typeSql = (depth < Type.MAX_NESTING_DEPTH) ? type_.toSql(depth) : "..."; |
| StringBuilder sb = new StringBuilder(name_); |
| if (type_ != null) sb.append(":" + typeSql); |
| if (comment_ != null) sb.append(String.format(" COMMENT '%s'", comment_)); |
| return sb.toString(); |
| } |
| |
| /** |
| * Pretty prints this field with lpad number of leading spaces. |
| * Calls prettyPrint(lpad) on this field's type. |
| */ |
| public String prettyPrint(int lpad) { |
| String leftPadding = StringUtils.repeat(' ', lpad); |
| StringBuilder sb = new StringBuilder(leftPadding + name_); |
| if (type_ != null) { |
| // Pass in the padding to make sure nested fields are aligned properly, |
| // even if we then strip the top-level padding. |
| String typeStr = type_.prettyPrint(lpad); |
| typeStr = typeStr.substring(lpad); |
| sb.append(":" + typeStr); |
| } |
| if (comment_ != null) sb.append(String.format(" COMMENT '%s'", comment_)); |
| return sb.toString(); |
| } |
| |
| public void toThrift(TColumnType container, TTypeNode node) { |
| TStructField field = new TStructField(); |
| field.setName(name_); |
| if (comment_ != null) field.setComment(comment_); |
| node.struct_fields.add(field); |
| type_.toThrift(container); |
| } |
| |
| @Override |
| public boolean equals(Object other) { |
| if (!(other instanceof StructField)) return false; |
| StructField otherStructField = (StructField) other; |
| return otherStructField.name_.equals(name_) && otherStructField.type_.equals(type_); |
| } |
| } |