All Downloads are FREE. Search and download functionalities are using the official Maven repository.

com.vaadin.ui.declarative.converters.DesignToStringConverter Maven / Gradle / Ivy

There is a newer version: 8.27.3
Show newest version
/*
 * 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 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 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 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();
        }
    }

}




© 2015 - 2024 Weber Informatics LLC | Privacy Policy