MapTemplateLocator.java

/*
 * Copyright 2013 Martin Kouba
 *
 * 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 org.trimou.engine.locator;

import java.io.Reader;
import java.io.StringReader;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/**
 * Template locator backed by a {@link Map}.
 *
 * @author Martin Kouba
 */
public class MapTemplateLocator extends AbstractTemplateLocator {

    /**
     * Name to contents map
     */
    private final Map<String, String> templates;

    /**
     *
     * @param priority
     * @param templates
     */
    public MapTemplateLocator(int priority, Map<String, String> templates) {
        super(priority);
        this.templates = templates;
    }

    /**
     *
     * @param templates
     */
    public MapTemplateLocator(Map<String, String> templates) {
        super(TemplateLocator.DEFAULT_PRIORITY);
        this.templates = templates;
    }

    @Override
    public Reader locate(String templateName) {
        String templateContent = templates.get(templateName);
        if (templateContent != null) {
            return new StringReader(templateContent);
        }
        return null;
    }

    @Override
    public Set<String> getAllIdentifiers() {
        return templates.keySet();
    }

    @Override
    public String toString() {
        return String.format("%s [priority: %s]", getClass().getName(),
                getPriority());
    }

    public static Builder builder() {
        return new Builder();
    }

    public static class Builder {

        private final Map<String, String> templates;

        private Builder() {
            this.templates = new HashMap<>();
        }

        public Builder put(String name, String template) {
            this.templates.put(name, template);
            return this;
        }

        public MapTemplateLocator build() {
            return new MapTemplateLocator(new HashMap<>(templates));
        }

    }

}