- /*
- * Copyright 2000-2016 Vaadin Ltd.
- *
- * 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 com.vaadin.ui.declarative.converters;
-
- import java.lang.reflect.InvocationTargetException;
- import java.util.Locale;
-
- import com.vaadin.data.Result;
- import com.vaadin.data.util.converter.Converter;
- import com.vaadin.ui.declarative.DesignAttributeHandler;
-
- /**
- * Utility class for {@link DesignAttributeHandler} that deals with converting
- * various types to string.
- *
- * @since 7.4
- * @author Vaadin Ltd
- * @param <TYPE>
- * Type of the data being converted.
- */
- public class DesignToStringConverter<TYPE> implements Converter<String, TYPE> {
-
- private final Class<? extends TYPE> type;
-
- private final String staticMethodName;
-
- /**
- * A string that corresponds to how a null value is stored.
- */
- public static final String NULL_VALUE_REPRESENTATION = "";
-
- /**
- * Constructs the converter for a given type. Implicitly requires that a
- * static method {@code valueOf(String)} is present in the type to do the
- * conversion.
- *
- * @param type
- * Type of values to convert.
- */
- public DesignToStringConverter(Class<? extends TYPE> type) {
- this(type, "valueOf");
- }
-
- /**
- * Constructs the converter for a given type, giving the name of the public
- * static method that does the conversion from String.
- *
- * @param type
- * Type to convert.
- * @param staticMethodName
- * Method to call when converting from String to this type. This
- * must be public and static method that returns an object of
- * passed type.
- */
- public DesignToStringConverter(Class<? extends TYPE> type,
- String staticMethodName) {
- this.type = type;
- this.staticMethodName = staticMethodName;
- }
-
- @Override
- public Result<TYPE> convertToModel(String value, Locale locale) {
- try {
- return Result.ok(type
- .cast(type.getMethod(this.staticMethodName, String.class)
- .invoke(null, value)));
- } catch (InvocationTargetException e) {
- return Result.error(e.getCause().getMessage());
- } catch (Exception e) {
- return Result.error(e.getMessage());
- }
- }
-
- @Override
- public String convertToPresentation(TYPE value, Locale locale) {
- if (value == null) {
- return NULL_VALUE_REPRESENTATION;
- } else {
- return value.toString();
- }
- }
-
- }
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