org.jclouds.deltacloud.xml.HardwarePropertyHandler.java Source code

Introduction

Here is the source code for org.jclouds.deltacloud.xml.HardwarePropertyHandler.java

Source

/**
 *
 * Copyright (C) 2010 Cloud Conscious, LLC. <info@cloudconscious.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.links/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.jclouds.deltacloud.xml;

import java.net.URI;
import java.util.Map;
import java.util.Set;
import java.util.regex.Pattern;

import javax.annotation.Nullable;

import org.jclouds.deltacloud.domain.EnumHardwareProperty;
import org.jclouds.deltacloud.domain.FixedHardwareProperty;
import org.jclouds.deltacloud.domain.HardwareParameter;
import org.jclouds.deltacloud.domain.HardwareProperty;
import org.jclouds.deltacloud.domain.HardwareProperty.Kind;
import org.jclouds.deltacloud.domain.RangeHardwareProperty;
import org.jclouds.http.functions.ParseSax;
import org.jclouds.util.SaxUtils;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;

import com.google.common.collect.Sets;

/**
 * @author Adrian Cole
 */
public class HardwarePropertyHandler extends ParseSax.HandlerWithResult<HardwareProperty> {
    private Kind kind;
    private String name;
    private String unit;
    private Object value;
    private HardwareParameter param;
    private Set<Object> availableValues = Sets.newLinkedHashSet();
    private Number first;
    private Number last;

    /**
     * resets state of the handler when called.
     * 
     * @return property or null
     */
    public HardwareProperty getResult() {
        try {
            switch (kind) {
            case FIXED:
                return new FixedHardwareProperty(name, unit, value);
            case ENUM:
                return new EnumHardwareProperty(name, unit, value, param, availableValues);
            case RANGE:
                return new RangeHardwareProperty(name, unit, (Number) value, param, first, last);
            default:
                return null;
            }
        } finally {
            this.kind = null;
            this.name = null;
            this.unit = null;
            this.value = null;
            this.param = null;
            this.availableValues = Sets.newLinkedHashSet();
            this.first = null;
            this.last = null;
        }
    }

    private static final Pattern LONG = Pattern.compile("^[0-9]+$");
    private static final Pattern DOUBLE = Pattern.compile("^[0-9]+\\.[0-9]+$");

    public static @Nullable Number parseNumberOrNull(String in) {
        if (DOUBLE.matcher(in).matches())
            return new Double(in);
        else if (LONG.matcher(in).matches())
            return new Long(in);
        return null;
    }

    @Override
    public void startElement(String uri, String localName, String qName, Attributes attrs) throws SAXException {
        Map<String, String> attributes = SaxUtils.cleanseAttributes(attrs);
        if (qName.equals("property")) {
            this.kind = Kind.fromValue(attributes.get("kind"));
            this.name = attributes.get("name");
            this.unit = attributes.get("unit");
            if (attributes.containsKey("value")) {
                this.value = stringOrNumber(attributes.get("value"));
            }
        } else if (qName.equals("param")) {
            this.param = new HardwareParameter(URI.create(attributes.get("href")), attributes.get("method"),
                    attributes.get("name"), attributes.get("operation"));
        } else if (qName.equals("range")) {
            this.first = parseNumberOrNull(attributes.get("first"));
            this.last = parseNumberOrNull(attributes.get("last"));
        } else if (qName.equals("entry")) {
            this.availableValues.add(stringOrNumber(attributes.get("value")));
        }
    }

    public static Object stringOrNumber(String in) {
        Number number = parseNumberOrNull(in);
        return number != null ? number : in;
    }
}