I18nSpringContext.java

package dev.orne.i18n.spring;

/*-
 * #%L
 * Orne I18N
 * %%
 * Copyright (C) 2021 Orne Developments
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Lesser Public License for more details.
 * 
 * You should have received a copy of the GNU General Lesser Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/lgpl-3.0.html>.
 * #L%
 */

import java.io.Serializable;
import java.util.Locale;
import java.util.UUID;

import javax.validation.constraints.NotNull;

import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.lang3.Validate;
import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;
import org.apache.commons.lang3.builder.ToStringBuilder;
import org.apache.commons.lang3.builder.ToStringStyle;
import org.apiguardian.api.API;
import org.apiguardian.api.API.Status;
import org.springframework.context.i18n.LocaleContextHolder;

import dev.orne.i18n.context.I18nContext;

/**
 * Implementation of {@code I18nContext} that delegates {@code Locale}
 * handling in Spring {@code LocaleContextHolder}.
 * 
 * @author <a href="https://github.com/ihernaez">(w) Iker Hernaez</a>
 * @version 1.0, 2021-01
 * @see I18nContext
 * @see LocaleContextHolder
 * @since 0.1
 */
@API(status=Status.STABLE, since="0.1")
public class I18nSpringContext
implements I18nContext, Serializable {

    /** The serial verion UID. */
    private static final long serialVersionUID = 1L;

    /** The UUID of the provider owner of this context. */
    private final @NotNull UUID providerUUID;

    /**
     * Creates a new instance.
     * 
     * @param providerUUID The UUID of the provider owner of this context
     */
    public I18nSpringContext(
            final @NotNull UUID providerUUID) {
        super();
        this.providerUUID = Validate.notNull(providerUUID);
    }

    /**
     * Copy constructor.
     * 
     * @param copy The instance to copy
     */
    public I18nSpringContext(
            final @NotNull I18nSpringContext copy) {
        super();
        Validate.notNull(copy);
        this.providerUUID = copy.providerUUID;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public @NotNull UUID getProviderUUID() {
        return this.providerUUID;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public @NotNull Locale getLocale() {
        return ObjectUtils.defaultIfNull(
                LocaleContextHolder.getLocale(),
                Locale.getDefault());
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void setLocale(final Locale locale) {
        LocaleContextHolder.setLocale(locale);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public int hashCode() {
        return new HashCodeBuilder()
                .append(this.providerUUID)
                .toHashCode();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean equals(final Object obj) {
        if (obj == null) { return false; }
        if (obj == this) { return true; }
        if (!getClass().equals(obj.getClass())) { return false; }
        final I18nSpringContext other = (I18nSpringContext) obj;
        return new EqualsBuilder()
                .append(this.providerUUID, other.providerUUID)
                .isEquals();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String toString() {
        return new ToStringBuilder(this, ToStringStyle.DEFAULT_STYLE)
                .append("locale", getLocale())
                .toString();
    }
}