PrismLog usage bug fixes.

For example, this was crashing:

prism % prism dice.pm -simpath 10 stdout

Author: davexparker

prism/src/simulator/GenerateSimulationPath.java

@@ -35,6 +35,7 @@
 import prism.PrismException;
 import prism.PrismFileLog;
 import prism.PrismLog;
+import prism.PrismLogWrapper;
 import userinterface.graph.Graph;
 
 /**
@@ -344,7 +345,7 @@ private PathDisplayer generateDisplayerForExport() throws PrismException
 		if (file != null) {
 			log = new PrismFileLog(file.getPath());
 		} else {
-			log = mainLog;
+			log = new PrismLogWrapper(mainLog);
 		}
 		displayer = new PathToText(log, engine.getModel(), engine.getRewardGenerator());
 		displayer.setColSep(simPathSep);

prism/src/simulator/PathToText.java

@@ -63,7 +63,8 @@ public class PathToText extends PathDisplayer
 	private boolean changed;
 
 	/**
-	 * Construct a {@link PathToText} object
+	 * Construct a {@link PathToText} object, which writes to a {@link PrismLog}.
+	 * The log will be {@code close()}d when {@link #close()} is called.
 	 * @param log Log to output path to
 	 * @param modelInfo Model associated with path
 	 * @param rewardGen Rewards associated with path

prism/src/simulator/SimulatorEngine.java

@@ -1678,24 +1678,12 @@ public void exportPath(File file, boolean timeCumul, String colSep, ArrayList<In
 	 */
 	public void exportPath(File file, boolean timeCumul, boolean showRewards, String colSep, ArrayList<Integer> vars) throws PrismException
 	{
-		PrismLog log = null;
-		try {
-			if (path == null)
-				throw new PrismException("There is no path to export");
-			// create new file log or use main log
-			if (file != null) {
-				log = new PrismFileLog(file.getPath());
-				mainLog.println("\nExporting path to file \"" + file + "\"...");
-			} else {
-				log = mainLog;
-				log.println();
-			}
+		if (path == null) {
+			throw new PrismException("There is no path to export");
+		}
+		try (PrismLog log = getPrismLogForFile(file)) {
+			mainLog.println("\nExporting path " + getDestinationStringForFile(file));
 			((PathFull) path).exportToLog(log, timeCumul, showRewards, colSep, vars);
-			if (file != null)
-				log.close();
-		} finally {
-			if (file != null && log != null)
-				log.close();
 		}
 	}