Parameters.java

/**
 *  Copyright 2012 Universitat Pompeu Fabra.
 *
 *  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.onexus.resource.api;

import java.util.HashMap;
import java.util.Map;

public class Parameters extends HashMap<ParameterKey, String> {

    public Parameters() {
        super();
    }

    public Parameters(Map<ParameterKey, String> map) {
        super(map);
    }

    public String get(Object key) {

        if (!(key instanceof ParameterKey)) {
            throw new UnsupportedOperationException("Key object must implement ParameterKey interface");
        }

        ParameterKey parameterKey = (ParameterKey) key;

        if (!parameterKey.isOptional() && !containsKey(key)) {
            throw new UnsupportedOperationException(
                    "Parameter '" + parameterKey.getKey() + " - " + parameterKey.getDescription() + "' is mandatory");
        }

        String value = super.get(key);

        if (value == null) {
            value = parameterKey.getDefault();
        }

        return value;
    }

}