add handling for error conditions

Author: gbburkhardt

src/gov/nasa/worldwind/util/DataConfigurationUtils.java

@@ -766,8 +766,9 @@ public static AVList getWMSLayerConfigParams(WMSCapabilities caps, String[] form
                 WMSLayerCapabilities layerCaps = caps.getLayerByName(name);
                 if (layerCaps == null)
                 {
-                    Logging.logger().warning(Logging.getMessage("WMS.LayerNameMissing", name));
-                    continue;
+                    String msg = Logging.getMessage("WMS.LayerNameMissing", name);
+                    Logging.logger().warning(msg);
+                    throw new WWRuntimeException(msg);
                 }
 
                 if (layerCaps.hasCoordinateSystem("EPSG:4326"))
@@ -916,6 +917,13 @@ public static AVList getWCSConfigParameters(WCS100Capabilities caps, WCS100Descr
             throw new IllegalArgumentException(message);
         }
 
+        if (coverage.getCoverageOfferings().size() == 0)
+        {
+        	String message = Logging.getMessage("AbsentResourceList.WCSDescribeCoverage");
+            Logging.logger().severe(message);
+            throw new IllegalArgumentException(message);
+        }
+
         if (params == null)
         {
             String message = Logging.getMessage("nullValue.ParametersIsNull");
@@ -1148,6 +1156,8 @@ protected static String makeTitle(WMSCapabilities caps, String layerNames, Strin
 
             String layerName = lNames[i];
             WMSLayerCapabilities layer = caps.getLayerByName(layerName);
+            if (layer == null) continue;		// layer not found
+
             String layerTitle = layer.getTitle();
             sb.append(layerTitle != null ? layerTitle : layerName);
 

src/gov/nasa/worldwind/util/MessageStrings.properties

@@ -743,6 +743,7 @@ AbsentResourceList.MaxTriesLessThanOne=The specified maximum number of tries is
 AbsentResourceList.CheckIntervalLessThanZero=The specified check interval is less than 0
 AbsentResourceList.RetryIntervalLessThanZero=The specified retry interval is less than 0
 AbsentResourceList.MaximumListSizeLessThanOne=The requested maximum list size is less than 1
+AbsentResourceList.WCSDescribeCoverage=No coverage offering from WCS
 
 AVAAccessibleImpl.AttributeValueForKeyIsNotAString=Attribute value for key is not a String. Key {0}
 

src/gov/nasa/worldwindx/examples/layermanager/ElevationModelManagerPanel.java

@@ -127,7 +127,8 @@ protected boolean isUpToDate(WorldWindow wwd)
 
         if (!(wwd.getModel().getGlobe().getElevationModel() instanceof CompoundElevationModel))
         {
-            return this.modelPanels.get(0).getElevationModel() == wwd.getModel().getGlobe().getElevationModel();
+           if (this.modelPanels.size() == 0) return false;
+           return this.modelPanels.get(0).getElevationModel() == wwd.getModel().getGlobe().getElevationModel();
         }
 
         CompoundElevationModel cem = (CompoundElevationModel) wwd.getModel().getGlobe().getElevationModel();

src/gov/nasa/worldwindx/examples/util/WCSCoveragePanel.java

@@ -100,7 +100,9 @@ protected void load()
         {
             e.printStackTrace();
             Container c = WCSCoveragePanel.this.getParent();
-            c.remove(WCSCoveragePanel.this);
+            if (c != null)
+            	c.remove(WCSCoveragePanel.this);
+            
             JOptionPane.showMessageDialog((Component) wwd, "Unable to connect to server " + serverURI.toString(),
                 "Server Error", JOptionPane.ERROR_MESSAGE);
             return;
@@ -192,8 +194,10 @@ public void actionPerformed(ActionEvent actionEvent)
             // If the coverage is selected, add it to the WorldWindow's current model, else remove it from the model.
             if (((JCheckBox) actionEvent.getSource()).isSelected())
             {
-                if (this.component == null)
+                if (this.component == null) {
                     this.component = createComponent(coverageInfo.caps, coverageInfo);
+                    if (this.component == null) return;
+                }
 
                 updateComponent(this.component, true);
             }
@@ -224,8 +228,18 @@ protected CoverageInfo createCoverageInfo(WCS100Capabilities caps, WCS100Coverag
     protected void updateComponent(Object component, boolean enable)
     {
         ElevationModel model = (ElevationModel) component;
-        CompoundElevationModel compoundModel =
-            (CompoundElevationModel) this.wwd.getModel().getGlobe().getElevationModel();
+        CompoundElevationModel compoundModel;
+
+        // Guarantee that we have a compound elevation model, so additional elevation models can be added.
+        ElevationModel em = this.wwd.getModel().getGlobe().getElevationModel();
+
+        if (!(em instanceof CompoundElevationModel)) {
+        	compoundModel = new CompoundElevationModel();
+        	compoundModel.addElevationModel(em);
+        	this.wwd.getModel().getGlobe().setElevationModel(compoundModel);
+        } else {
+        	compoundModel = (CompoundElevationModel) em;
+        }
 
         if (enable)
         {