| /* |
| * 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.wayang.basic.types; |
| |
| import org.apache.wayang.basic.data.Record; |
| import org.apache.wayang.core.types.BasicDataUnitType; |
| |
| import java.util.Arrays; |
| import java.util.Objects; |
| |
| /** |
| * This is a specific {@link BasicDataUnitType} for {@link Record}s. In particular, it adds schema information. |
| */ |
| public class RecordType extends BasicDataUnitType<Record> { |
| |
| /** |
| * Names of fields in the described {@link Record}s in order of appearance. |
| */ |
| private String[] fieldNames; |
| |
| /** |
| * Creates a new instance. |
| * |
| * @param fieldNames names of fields in the described {@link Record}s in order of appearance |
| */ |
| public RecordType(String... fieldNames) { |
| super(Record.class); |
| this.fieldNames = fieldNames; |
| } |
| |
| public String[] getFieldNames() { |
| return this.fieldNames; |
| } |
| |
| @Override |
| public boolean isSupertypeOf(BasicDataUnitType<?> that) { |
| // A RecordType cannot have subtypes. |
| return this.equals(that); |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (this == o) return true; |
| if (o == null || getClass() != o.getClass()) return false; |
| if (!super.equals(o)) return false; |
| RecordType that = (RecordType) o; |
| return Arrays.equals(fieldNames, that.fieldNames); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(super.hashCode(), fieldNames); |
| } |
| |
| @Override |
| public String toString() { |
| return "RecordType" + Arrays.toString(fieldNames); |
| } |
| |
| /** |
| * Returns the index of a field according to this instance. |
| * |
| * @param fieldName the name of the field |
| * @return the index of the field |
| */ |
| public int getIndex(String fieldName) { |
| for (int i = 0; i < this.fieldNames.length; i++) { |
| String name = this.fieldNames[i]; |
| if (name.equals(fieldName)) { |
| return i; |
| } |
| } |
| throw new IllegalArgumentException(String.format("No such field \"%s\" in %s.", fieldName, this)); |
| } |
| } |