/*
* Copyright 2015 the original author or authors.
*
* 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
*
* 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.springframework.cloud.stream.module.jdbc;
import java.util.LinkedHashMap;
import java.util.Map;
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.core.convert.converter.ConditionalConverter;
import org.springframework.core.convert.converter.Converter;
import org.springframework.util.Assert;
/**
* A Converter from String to Map that accepts csv {@literal key:value} pairs
* (similar to what comes out of the box in Spring Core) but also simple
* {@literal key} items, in which case the value is assumed to be equal to the key.
*
* <p>Additionally, commas and colons can be escaped by using a backslash, which is
* useful if said mappings are to be used for SpEL for example.</p>
*
* @author Eric Bottard
*/
public class ShorthandMapConverter implements Converter<String, Map<String, String>>, ConditionalConverter{
@Override
public Map<String, String> convert(String source) {
Map<String, String> result = new LinkedHashMap<>();
// Split on comma if not preceded by backslash
String[] mappings = source.split("(?<!\\\\),");
for (String mapping : mappings) {
// Turn backslash-comma back to comma
String unescaped = mapping.trim().replace("\\,", ",");
if (unescaped.length() == 0) {
continue;
}
// Split on colon, if not preceded by backslash
String[] keyValuePair = unescaped.split("(?<!\\\\):");
Assert.isTrue(keyValuePair.length <= 2, "'" + unescaped +
"' could not be parsed to a 'key:value' pair or simple 'key' with implicit value");
String key = keyValuePair[0].trim().replace("\\:", ":");
String value = keyValuePair.length == 2 ? keyValuePair[1].trim().replace("\\:", ":") : key;
result.put(key, value);
}
return result;
}
@Override
public boolean matches(TypeDescriptor sourceType, TypeDescriptor targetType) {
return targetType.hasAnnotation(SupportsShorthands.class);
}
}