com.vaadin.ui.declarative.converters.DesignToStringConverter Maven / Gradle / Ivy
/*
* Copyright (C) 2000-2024 Vaadin Ltd
*
* This program is available under Vaadin Commercial License and Service Terms.
*
* See for the full
* license.
*/
package com.vaadin.ui.declarative.converters;
import java.lang.reflect.InvocationTargetException;
import com.vaadin.data.Converter;
import com.vaadin.data.Result;
import com.vaadin.data.ValueContext;
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 of the data being converted.
*/
public class DesignToStringConverter implements Converter {
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 convertToModel(String value, ValueContext context) {
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, ValueContext context) {
if (value == null) {
return NULL_VALUE_REPRESENTATION;
} else {
return value.toString();
}
}
}