de.vandermeer.skb.interfaces.messagesets.IsErrorSet.java Source code

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Here is the source code for de.vandermeer.skb.interfaces.messagesets.IsErrorSet.java

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/* Copyright 2016 Sven van der Meer <vdmeer.sven@mykolab.com>
 *
 * 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 de.vandermeer.skb.interfaces.messagesets;

import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.Set;

import org.apache.commons.lang3.text.StrBuilder;

import de.vandermeer.skb.interfaces.render.DoesRender;

/**
 * Interface for objects that have a set of error messages.
 *
 * @author     Sven van der Meer &lt;vdmeer.sven@mykolab.com&gt;
 * @version    v0.0.2 build 170502 (02-May-17) for Java 1.8
 * @since      v0.0.1
 */
public interface IsErrorSet<M> extends IsMessageSet {

    /**
     * Clears all errors.
     */
    default void clearErrorMessages() {
        this.getErrorMessages().clear();
    }

    /**
     * Returns the error set.
     * @return error set, should not be null
     */
    Set<M> getErrorMessages();

    /**
     * Adds a new error.
     * @param error error to add
     */
    default void addError(M error) {
        this.getErrorMessages().add(error);
    }

    /**
     * Adds all errors from given collection.
     * @param errors collection of errors to add
     */
    default void addAllErrors(Collection<M> errors) {
        this.getErrorMessages().addAll(errors);
    }

    /**
     * Tests if errors have been added.
     * @return true if errors are in the set, false otherwise
     */
    default boolean hasErrors() {
        return (this.getErrorMessages().size() == 0) ? false : true;
    }

    /**
     * Renders the error set.
     * The method uses {@link DoesRender} or simple toString to render errors.
     * Each element in the error set is rendered in a single line.
     * @return rendered object
     */
    @Override
    default String render() {
        StrBuilder ret = new StrBuilder(100);
        for (M m : this.getErrorMessages()) {
            if (m instanceof DoesRender) {
                ret.append(((DoesRender) m).render());
            } else {
                ret.append(m);
            }
            ret.appendNewLine();
        }
        return ret.toString();
    }

    /**
     * Creates a new error set.
     * @param <M> type of the messages in the set
     * @return new error set
     */
    static <M> IsErrorSet<M> create() {
        return new IsErrorSet<M>() {
            final Set<M> errorSet = new LinkedHashSet<>();

            @Override
            public Set<M> getErrorMessages() {
                return this.errorSet;
            }
        };
    }
}