Use CompletionService to fail early when a thread crashes (#980)

* Changed Runnable to Callable
* Use isInterrupted

core/src/main/java/com/graphhopper/routing/ch/CHAlgoFactoryDecorator.java

@@ -32,8 +32,7 @@
 import org.slf4j.LoggerFactory;
 
 import java.util.*;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.TimeUnit;
+import java.util.concurrent.*;
 
 import static com.graphhopper.util.Parameters.CH.DISABLE;
 
@@ -279,38 +278,41 @@ public void setPreparationThreads(int preparationThreads) {
     }
 
     public void prepare(final StorableProperties properties) {
+        ExecutorCompletionService completionService = new ExecutorCompletionService<>(threadPool);
         int counter = 0;
         for (final PrepareContractionHierarchies prepare : getPreparations()) {
             LOGGER.info((++counter) + "/" + getPreparations().size() + " calling CH prepare.doWork for " + prepare.getWeighting() + " ... (" + Helper.getMemInfo() + ")");
             final String name = AbstractWeighting.weightingToFileName(prepare.getWeighting());
-            threadPool.execute(new Runnable() {
+            completionService.submit(new Runnable() {
                 @Override
                 public void run() {
                     String errorKey = CH.PREPARE + "error." + name;
                     try {
                         // toString is not taken into account so we need to cheat, see http://stackoverflow.com/q/6113746/194609 for other options
                         Thread.currentThread().setName(name);
-
                         properties.put(errorKey, "CH preparation incomplete");
                         prepare.doWork();
                         properties.remove(errorKey);
                         properties.put(CH.PREPARE + "date." + name, Helper.createFormatter().format(new Date()));
                     } catch (Exception ex) {
                         LOGGER.error("Problem while CH preparation " + name, ex);
                         properties.put(errorKey, ex.getMessage());
+                        throw ex;
                     }
                 }
-            });
+            }, name);
+
         }
 
         threadPool.shutdown();
-        try {
-            if (!threadPool.awaitTermination(Integer.MAX_VALUE, TimeUnit.DAYS))
-                threadPool.shutdownNow();
 
-        } catch (InterruptedException ie) {
+        try {
+            for (int i = 0; i < getPreparations().size(); i++) {
+                completionService.take().get();
+            }
+        } catch (Exception e) {
             threadPool.shutdownNow();
-            throw new RuntimeException(ie);
+            throw new RuntimeException(e);
         }
     }
 

core/src/main/java/com/graphhopper/routing/ch/PrepareContractionHierarchies.java

@@ -304,6 +304,11 @@ void contractNodes() {
 
             CHEdgeIterator iter = vehicleAllExplorer.setBaseNode(polledNode);
             while (iter.next()) {
+
+                if(Thread.currentThread().isInterrupted()){
+                    throw new RuntimeException("Thread was interrupted");
+                }
+
                 int nn = iter.getAdjNode();
                 if (prepareGraph.getLevel(nn) != maxLevel)
                     continue;