| <!-- |
| ~ 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. |
| --> |
| |
| <html> |
| <h2>Flatten</h2> |
| <p> |
| Flatten is a Beam transform for PCollection objects that store the same data type. |
| Flatten merges multiple PCollection objects into a single logical PCollection. |
| </p> |
| <p> |
| <b>Kata:</b> Implement a |
| <a href="https://beam.apache.org/releases/javadoc/current/org/apache/beam/sdk/transforms/Flatten.html"> |
| Flatten</a> transform that merges two PCollection of words into a single PCollection. |
| </p> |
| <br> |
| <div class="hint"> |
| Refer to |
| <a href="https://beam.apache.org/releases/javadoc/current/org/apache/beam/sdk/transforms/Flatten.html"> |
| Flatten</a> to solve this problem. |
| </div> |
| <div class="hint"> |
| Refer to the Beam Programming Guide |
| <a href="https://beam.apache.org/documentation/programming-guide/#flatten"> |
| "Flatten"</a> section for more information. |
| </div> |
| </html> |