/**
* 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.exec.store.easy.text.compliant;
/* Base class for producing output record batches while dealing with
* Text files.
*/
abstract class TextOutput {
static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(TextOutput.class);
/**
* Start processing a new field within a record.
* @param index index within the record
*/
public abstract void startField(int index);
/**
* End processing a field within a record.
* @return true if engine should continue processing record. false if rest of record can be skipped.
*/
public abstract boolean endField();
/**
* Shortcut that lets the output know that we are closing ending a field with no data.
* @return true if engine should continue processing record. false if rest of record can be skipped.
*/
public abstract boolean endEmptyField();
/**
* Add the provided data but drop any whitespace.
* @param data
*/
public void appendIgnoringWhitespace(byte data){
if(TextReader.isWhite(data)){
// noop
}else{
append(data);
}
}
/**
* This function appends the byte to the output character data buffer
* @param data current byte read
*/
public abstract void append(byte data);
/**
* Completes the processing of a given record. Also completes the processing of the
* last field being read.
*/
public abstract void finishRecord();
/**
* Return the total number of records (across batches) processed
*/
public abstract long getRecordCount();
/**
* Informs output to setup for new record batch.
*/
public abstract void startBatch();
/**
* Does any final cleanup that is required for closing a batch. Example might include closing the last field.
*/
public abstract void finishBatch();
/**
* Helper method to check if the current record has any non-empty fields
*/
public abstract boolean rowHasData();
}