org.argeo.cms/src/org/argeo/cms/internal/kernel/DataModels.java

   1 package org.argeo.cms.internal.kernel;
   2
   3 import static org.argeo.api.DataModelNamespace.CMS_DATA_MODEL_NAMESPACE;
   4
   5 import java.util.ArrayList;
   6 import java.util.Collections;
   7 import java.util.List;
   8 import java.util.Map;
   9 import java.util.TreeMap;
  10
  11 import org.apache.commons.logging.Log;
  12 import org.apache.commons.logging.LogFactory;
  13 import org.argeo.api.DataModelNamespace;
  14 import org.argeo.cms.CmsException;
  15 import org.osgi.framework.Bundle;
  16 import org.osgi.framework.BundleContext;
  17 import org.osgi.framework.BundleEvent;
  18 import org.osgi.framework.BundleListener;
  19 import org.osgi.framework.wiring.BundleCapability;
  20 import org.osgi.framework.wiring.BundleWire;
  21 import org.osgi.framework.wiring.BundleWiring;
  22
  23 class DataModels implements BundleListener {
  24         private final static Log log = LogFactory.getLog(DataModels.class);
  25
  26         private Map<String, DataModel> dataModels = new TreeMap<>();
  27
  28         public DataModels(BundleContext bc) {
  29                 for (Bundle bundle : bc.getBundles())
  30                         processBundle(bundle, null);
  31                 bc.addBundleListener(this);
  32         }
  33
  34         public List<DataModel> getNonAbstractDataModels() {
  35                 List<DataModel> res = new ArrayList<>();
  36                 for (String name : dataModels.keySet()) {
  37                         DataModel dataModel = dataModels.get(name);
  38                         if (!dataModel.isAbstract())
  39                                 res.add(dataModel);
  40                 }
  41                 // TODO reorder?
  42                 return res;
  43         }
  44
  45         @Override
  46         public void bundleChanged(BundleEvent event) {
  47                 if (event.getType() == Bundle.RESOLVED) {
  48                         processBundle(event.getBundle(), null);
  49                 } else if (event.getType() == Bundle.UNINSTALLED) {
  50                         BundleWiring wiring = event.getBundle().adapt(BundleWiring.class);
  51                         List<BundleCapability> providedDataModels = wiring.getCapabilities(CMS_DATA_MODEL_NAMESPACE);
  52                         if (providedDataModels.size() == 0)
  53                                 return;
  54                         for (BundleCapability bundleCapability : providedDataModels) {
  55                                 dataModels.remove(bundleCapability.getAttributes().get(DataModelNamespace.NAME));
  56                         }
  57                 }
  58
  59         }
  60
  61         protected void processBundle(Bundle bundle, List<Bundle> scannedBundles) {
  62                 if (scannedBundles != null && scannedBundles.contains(bundle))
  63                         throw new IllegalStateException("Cycle in CMS data model requirements for " + bundle);
  64                 BundleWiring wiring = bundle.adapt(BundleWiring.class);
  65                 if (wiring == null) {
  66                         int bundleState = bundle.getState();
  67                         if (bundleState != Bundle.INSTALLED && bundleState != Bundle.UNINSTALLED) {// ignore unresolved bundles
  68                                 log.warn("Bundle " + bundle.getSymbolicName() + " #" + bundle.getBundleId() + " ("
  69                                                 + bundle.getLocation() + ") cannot be adapted to a wiring");
  70                         } else {
  71                                 if (log.isTraceEnabled())
  72                                         log.warn("Bundle " + bundle.getSymbolicName() + " is not resolved.");
  73                         }
  74                         return;
  75                 }
  76                 List<BundleCapability> providedDataModels = wiring.getCapabilities(CMS_DATA_MODEL_NAMESPACE);
  77                 if (providedDataModels.size() == 0)
  78                         return;
  79                 List<BundleWire> requiredDataModels = wiring.getRequiredWires(CMS_DATA_MODEL_NAMESPACE);
  80                 // process requirements first
  81                 for (BundleWire bundleWire : requiredDataModels) {
  82                         List<Bundle> nextScannedBundles = new ArrayList<>();
  83                         if (scannedBundles != null)
  84                                 nextScannedBundles.addAll(scannedBundles);
  85                         nextScannedBundles.add(bundle);
  86                         Bundle providerBundle = bundleWire.getProvider().getBundle();
  87                         processBundle(providerBundle, nextScannedBundles);
  88                 }
  89                 for (BundleCapability bundleCapability : providedDataModels) {
  90                         String name = (String) bundleCapability.getAttributes().get(DataModelNamespace.NAME);
  91                         assert name != null;
  92                         if (!dataModels.containsKey(name)) {
  93                                 DataModel dataModel = new DataModel(name, bundleCapability, requiredDataModels);
  94                                 dataModels.put(dataModel.getName(), dataModel);
  95                         }
  96                 }
  97         }
  98
  99         /** Return a negative depth if dataModel is required by ref, 0 otherwise. */
 100         static int required(DataModel ref, DataModel dataModel, int depth) {
 101                 for (DataModel dm : ref.getRequired()) {
 102                         if (dm.equals(dataModel))// found here
 103                                 return depth - 1;
 104                         int d = required(dm, dataModel, depth - 1);
 105                         if (d != 0)// found deeper
 106                                 return d;
 107                 }
 108                 return 0;// not found
 109         }
 110
 111         class DataModel {
 112                 private final String name;
 113                 private final boolean abstrct;
 114                 // private final boolean standalone;
 115                 private final String cnd;
 116                 private final List<DataModel> required;
 117
 118                 private DataModel(String name, BundleCapability bundleCapability, List<BundleWire> requiredDataModels) {
 119                         assert CMS_DATA_MODEL_NAMESPACE.equals(bundleCapability.getNamespace());
 120                         this.name = name;
 121                         Map<String, Object> attrs = bundleCapability.getAttributes();
 122                         abstrct = KernelUtils.asBoolean((String) attrs.get(DataModelNamespace.ABSTRACT));
 123                         // standalone = KernelUtils.asBoolean((String)
 124                         // attrs.get(DataModelNamespace.CAPABILITY_STANDALONE_ATTRIBUTE));
 125                         cnd = (String) attrs.get(DataModelNamespace.CND);
 126                         List<DataModel> req = new ArrayList<>();
 127                         for (BundleWire wire : requiredDataModels) {
 128                                 String requiredDataModelName = (String) wire.getCapability().getAttributes()
 129                                                 .get(DataModelNamespace.NAME);
 130                                 assert requiredDataModelName != null;
 131                                 DataModel requiredDataModel = dataModels.get(requiredDataModelName);
 132                                 if (requiredDataModel == null)
 133                                         throw new CmsException("No required data model " + requiredDataModelName);
 134                                 req.add(requiredDataModel);
 135                         }
 136                         required = Collections.unmodifiableList(req);
 137                 }
 138
 139                 public String getName() {
 140                         return name;
 141                 }
 142
 143                 public boolean isAbstract() {
 144                         return abstrct;
 145                 }
 146
 147                 // public boolean isStandalone() {
 148                 // return !isAbstract();
 149                 // }
 150
 151                 public String getCnd() {
 152                         return cnd;
 153                 }
 154
 155                 public List<DataModel> getRequired() {
 156                         return required;
 157                 }
 158
 159                 // @Override
 160                 // public int compareTo(DataModel o) {
 161                 // if (equals(o))
 162                 // return 0;
 163                 // int res = required(this, o, 0);
 164                 // if (res != 0)
 165                 // return res;
 166                 // // the other way round
 167                 // res = required(o, this, 0);
 168                 // if (res != 0)
 169                 // return -res;
 170                 // return 0;
 171                 // }
 172
 173                 @Override
 174                 public int hashCode() {
 175                         return name.hashCode();
 176                 }
 177
 178                 @Override
 179                 public boolean equals(Object obj) {
 180                         if (obj instanceof DataModel)
 181                                 return ((DataModel) obj).name.equals(name);
 182                         return false;
 183                 }
 184
 185                 @Override
 186                 public String toString() {
 187                         return "Data model " + name;
 188                 }
 189
 190         }
 191
 192 }