BooleanObjectArrayStringConverterFactory.java
/*
* Copyright 2010-present Stephen Colebourne
*
* 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.joda.convert.factory;
import org.joda.convert.StringConverter;
import org.joda.convert.StringConverterFactory;
import org.joda.convert.TypedStringConverter;
/**
* Factory for {@code StringConverter} providing support for Boolean object array
* as a sequence of 'T', 'F' and '-' for null.
* <p>
* This is intended as a human readable format, not a compact format.
* <p>
* To use, simply register the instance with a {@code StringConvert} instance.
* <p>
* This class is immutable and thread-safe.
*
* @since 1.5
*/
public final class BooleanObjectArrayStringConverterFactory implements StringConverterFactory {
/**
* Singleton instance.
*/
public static final StringConverterFactory INSTANCE = new BooleanObjectArrayStringConverterFactory();
/**
* Restricted constructor.
*/
private BooleanObjectArrayStringConverterFactory() {
}
//-----------------------------------------------------------------------
/**
* Finds a converter by type.
*
* @param cls the type to lookup, not null
* @return the converter, null if not found
* @throws RuntimeException (or subclass) if source code is invalid
*/
@Override
public StringConverter<?> findConverter(Class<?> cls) {
if (cls == Boolean[].class) {
return BooleanArrayStringConverter.INSTANCE;
}
return null;
}
//-----------------------------------------------------------------------
@Override
public String toString() {
return getClass().getSimpleName();
}
//-----------------------------------------------------------------------
enum BooleanArrayStringConverter implements TypedStringConverter<Boolean[]> {
INSTANCE {
@Override
public String convertToString(Boolean[] array) {
if (array.length == 0) {
return "";
}
StringBuilder buf = new StringBuilder(array.length);
for (int i = 0; i < array.length; i++) {
buf.append(array[i] == null ? '-' : (array[i].booleanValue() ? 'T' : 'F'));
}
return buf.toString();
}
@Override
public Boolean[] convertFromString(Class<? extends Boolean[]> cls, String str) {
if (str.length() == 0) {
return EMPTY;
}
Boolean[] array = new Boolean[str.length()];
for (int i = 0; i < array.length; i++) {
char ch = str.charAt(i);
if (ch == 'T') {
array[i] = Boolean.TRUE;
} else if (ch == 'F') {
array[i] = Boolean.FALSE;
} else if (ch == '-') {
array[i] = null;
} else {
throw new IllegalArgumentException("Invalid Boolean[] string, must consist only of 'T', 'F' and '-'");
}
}
return array;
}
@Override
public Class<?> getEffectiveType() {
return Boolean[].class;
}
};
private static final Boolean[] EMPTY = new Boolean[0];
}
}