| 1 | /* |
| 2 | * Copyright (c) 2009 The JOMC Project |
| 3 | * Copyright (c) 2005 Christian Schulte <cs@jomc.org> |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions |
| 8 | * are met: |
| 9 | * |
| 10 | * o Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * |
| 13 | * o Redistributions in binary form must reproduce the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer in |
| 15 | * the documentation and/or other materials provided with the |
| 16 | * distribution. |
| 17 | * |
| 18 | * THIS SOFTWARE IS PROVIDED BY THE JOMC PROJECT AND CONTRIBUTORS "AS IS" |
| 19 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| 20 | * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 21 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE JOMC PROJECT OR |
| 22 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| 23 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 24 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
| 25 | * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 26 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| 27 | * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| 28 | * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 29 | * |
| 30 | * $Id: DefaultServiceProvider.java 1393 2010-01-27 18:34:30Z schulte2005 $ |
| 31 | * |
| 32 | */ |
| 33 | package org.jomc.model.bootstrap; |
| 34 | |
| 35 | import java.net.URL; |
| 36 | import java.util.Enumeration; |
| 37 | import javax.xml.bind.JAXBContext; |
| 38 | import javax.xml.bind.JAXBElement; |
| 39 | import javax.xml.bind.JAXBException; |
| 40 | import javax.xml.bind.Unmarshaller; |
| 41 | |
| 42 | /** |
| 43 | * Default {@code ServiceProvider} implementation. |
| 44 | * |
| 45 | * @author <a href="mailto:cs@jomc.org">Christian Schulte</a> |
| 46 | * @version $Id: DefaultServiceProvider.java 1393 2010-01-27 18:34:30Z schulte2005 $ |
| 47 | * @see BootstrapContext#findServices() |
| 48 | */ |
| 49 | public class DefaultServiceProvider implements ServiceProvider |
| 50 | { |
| 51 | |
| 52 | /** |
| 53 | * Classpath location searched for services by default. |
| 54 | * @see #getDefaultServiceLocation() |
| 55 | */ |
| 56 | private static final String DEFAULT_SERVICE_LOCATION = "META-INF/jomc-services.xml"; |
| 57 | |
| 58 | /** Default service location. */ |
| 59 | private static volatile String defaultServiceLocation; |
| 60 | |
| 61 | /** Service location of the instance. */ |
| 62 | private String serviceLocation; |
| 63 | |
| 64 | /** Creates a new {@code DefaultServiceProvider} instance. */ |
| 65 | public DefaultServiceProvider() |
| 66 | { |
| 67 | super(); |
| 68 | } |
| 69 | |
| 70 | /** |
| 71 | * Gets the default location searched for service resources. |
| 72 | * <p>The default service location is controlled by system property |
| 73 | * {@code org.jomc.model.bootstrap.DefaultServiceProvider.defaultServiceLocation} holding the location to search for |
| 74 | * service resources by default. If that property is not set, the {@code META-INF/jomc-services.xml} default is |
| 75 | * returned.</p> |
| 76 | * |
| 77 | * @return The location searched for service resources by default. |
| 78 | * |
| 79 | * @see #setDefaultServiceLocation(java.lang.String) |
| 80 | */ |
| 81 | public static String getDefaultServiceLocation() |
| 82 | { |
| 83 | if ( defaultServiceLocation == null ) |
| 84 | { |
| 85 | defaultServiceLocation = System.getProperty( |
| 86 | "org.jomc.model.bootstrap.DefaultServiceProvider.defaultServiceLocation", DEFAULT_SERVICE_LOCATION ); |
| 87 | |
| 88 | } |
| 89 | |
| 90 | return defaultServiceLocation; |
| 91 | } |
| 92 | |
| 93 | /** |
| 94 | * Sets the default location searched for service resources. |
| 95 | * |
| 96 | * @param value The new default location to search for service resources or {@code null}. |
| 97 | * |
| 98 | * @see #getDefaultServiceLocation() |
| 99 | */ |
| 100 | public static void setDefaultServiceLocation( final String value ) |
| 101 | { |
| 102 | defaultServiceLocation = value; |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * Gets the location searched for service resources. |
| 107 | * |
| 108 | * @return The location searched for service resources. |
| 109 | * |
| 110 | * @see #getDefaultServiceLocation() |
| 111 | * @see #setServiceLocation(java.lang.String) |
| 112 | */ |
| 113 | public String getServiceLocation() |
| 114 | { |
| 115 | if ( this.serviceLocation == null ) |
| 116 | { |
| 117 | this.serviceLocation = getDefaultServiceLocation(); |
| 118 | } |
| 119 | |
| 120 | return this.serviceLocation; |
| 121 | } |
| 122 | |
| 123 | /** |
| 124 | * Sets the location searched for service resources. |
| 125 | * |
| 126 | * @param value The new location to search for service resources or {@code null}. |
| 127 | * |
| 128 | * @see #getServiceLocation() |
| 129 | */ |
| 130 | public void setServiceLocation( final String value ) |
| 131 | { |
| 132 | this.serviceLocation = value; |
| 133 | } |
| 134 | |
| 135 | /** |
| 136 | * Searches a given context for services. |
| 137 | * |
| 138 | * @param context The context to search for services. |
| 139 | * @param location The location to search at. |
| 140 | * |
| 141 | * @return The services found at {@code location} in {@code context} or {@code null} of no services are found. |
| 142 | * |
| 143 | * @throws NullPointerException if {@code context} or {@code location} is {@code null}. |
| 144 | * @throws BootstrapException if searching the context fails. |
| 145 | */ |
| 146 | public Services findServices( final BootstrapContext context, final String location ) throws BootstrapException |
| 147 | { |
| 148 | if ( context == null ) |
| 149 | { |
| 150 | throw new NullPointerException( "context" ); |
| 151 | } |
| 152 | if ( location == null ) |
| 153 | { |
| 154 | throw new NullPointerException( "location" ); |
| 155 | } |
| 156 | |
| 157 | try |
| 158 | { |
| 159 | final Services services = new Services(); |
| 160 | final JAXBContext ctx = context.createContext(); |
| 161 | final Unmarshaller u = ctx.createUnmarshaller(); |
| 162 | final Enumeration<URL> e = context.findResources( location ); |
| 163 | u.setSchema( context.createSchema() ); |
| 164 | |
| 165 | while ( e.hasMoreElements() ) |
| 166 | { |
| 167 | final URL url = e.nextElement(); |
| 168 | Object content = u.unmarshal( url ); |
| 169 | if ( content instanceof JAXBElement ) |
| 170 | { |
| 171 | content = ( (JAXBElement) content ).getValue(); |
| 172 | } |
| 173 | |
| 174 | if ( content instanceof Service ) |
| 175 | { |
| 176 | services.getService().add( (Service) content ); |
| 177 | } |
| 178 | else if ( content instanceof Services ) |
| 179 | { |
| 180 | for ( Service s : ( (Services) content ).getService() ) |
| 181 | { |
| 182 | services.getService().add( s ); |
| 183 | } |
| 184 | } |
| 185 | } |
| 186 | |
| 187 | return services.getService().isEmpty() ? null : services; |
| 188 | } |
| 189 | catch ( final JAXBException e ) |
| 190 | { |
| 191 | throw new BootstrapException( e ); |
| 192 | } |
| 193 | } |
| 194 | |
| 195 | /** |
| 196 | * {@inheritDoc} |
| 197 | * |
| 198 | * @see #getServiceLocation() |
| 199 | * @see #findServices(org.jomc.model.bootstrap.BootstrapContext, java.lang.String) |
| 200 | */ |
| 201 | public Services findServices( final BootstrapContext context ) throws BootstrapException |
| 202 | { |
| 203 | if ( context == null ) |
| 204 | { |
| 205 | throw new NullPointerException( "context" ); |
| 206 | } |
| 207 | |
| 208 | return this.findServices( context, this.getServiceLocation() ); |
| 209 | } |
| 210 | |
| 211 | } |