com.ebay.ejmask.extenstion.builder.AbstractRegexPatternBuilder Maven / Gradle / Ivy
package com.ebay.ejmask.extenstion.builder;
/**
* Copyright (c) 2023 eBay Inc.
*
* Licensed 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
*
* https://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.
*/
import com.ebay.ejmask.api.IPatternBuilder;
import com.ebay.ejmask.core.util.CommonUtils;
import java.util.HashSet;
/**
* Host common builder helper methods.
*/
public abstract class AbstractRegexPatternBuilder implements IPatternBuilder {
private static final String BLANK = "";
private static final String SEPARATOR = "|";
private static final int DEFAULT_CAPACITY = 500;
/**
* Convert the given list of fieldNames to regex or condition strings
*
* @param fieldNames as an array of fieldNames
* @return single regex or condition
*/
protected String buildFieldNamesForRegexOr(String... fieldNames) {
if (CommonUtils.isAnEmptyArray(fieldNames)) {
throw new IllegalArgumentException("empty / null fieldNames is not allowed.");
}
StringBuilder fieldBuilder = new StringBuilder(DEFAULT_CAPACITY);
String separator = BLANK;
HashSet keywords = new HashSet<>();
for (String fieldName : fieldNames) {
//check for duplicates
if (CommonUtils.isNotBlank(fieldName) && (!keywords.contains(fieldName))) {
fieldBuilder.append(separator).append(fieldName);
separator = SEPARATOR;
keywords.add(fieldName);
}
}
//in case of the list is full for blanks and nulls. this hardly ever happen
if (fieldBuilder.length() == 0) {
throw new IllegalArgumentException("empty set of fieldNames.");
}
return fieldBuilder.toString();
}
}