Centralize ij.IJ calls in ImpUtils

src/main/java/sc/fiji/snt/gui/DemoRunner.java

@@ -37,6 +37,7 @@
 import sc.fiji.snt.SNTUI;
 import sc.fiji.snt.Tree;
 import sc.fiji.snt.gui.cmds.SpotSpineLoaderCmd;
+import sc.fiji.snt.util.ImpUtils;
 
 public class DemoRunner {
 
@@ -246,7 +247,7 @@ private Demo demo9() {
 		final Demo entry = new Demo(9, "Non-neuronal dividing cell (5D image)") {
 			@Override
 			public ImagePlus getImage() {
-				final ImagePlus imp = ij.IJ.openImage("http://wsr.imagej.net/images/mitosis.tif");
+				final ImagePlus imp = ImpUtils.open("http://wsr.imagej.net/images/mitosis.tif");
 				imp.setPosition(2, 4, 31); // k-fibers channel, mid Z-range, traced time point
 				return imp;
 			}
@@ -306,7 +307,7 @@ private Demo demo11() {
 		final Demo entry = new Demo(11, "NeuronJ dataset (2D neurites)") {
 			@Override
 			public ImagePlus getImage() {
-				return  ij.IJ.openImage("https://github.com/morphonets/misc/raw/master/dataset-demos/NeuronJ/neurites.tif");
+				return  ImpUtils.open("https://github.com/morphonets/misc/raw/master/dataset-demos/NeuronJ/neurites.tif");
 			}
 			@Override
 			public void load() {
@@ -330,7 +331,7 @@ private Demo demo12() {
 		final Demo entry = new Demo(12, "Spot Spine dataset (spine decorated dendrite)") {
 			@Override
 			public ImagePlus getImage() {
-				return  ij.IJ.openImage("https://github.com/morphonets/misc/raw/master/dataset-demos/SpotSpine/SpotSpine_ImageStack_Test.tif");
+				return  ImpUtils.open("https://github.com/morphonets/misc/raw/master/dataset-demos/SpotSpine/SpotSpine_ImageStack_Test.tif");
 			}
 
 			@Override

src/main/java/sc/fiji/snt/hyperpanes/MultiDThreePanes.java

@@ -771,7 +771,7 @@ public static ImagePlus[] getZYXZ(final ImagePlus xy, final int frame) {
 	public static void main(final String[] args) {
 		if (ij.IJ.getInstance() == null) new ij.ImageJ();
 		final String path = "https://imagej.net/images/Spindly-GFP.zip";
-		final ImagePlus imp = ij.IJ.openImage(path);
+		final ImagePlus imp = sc.fiji.snt.util.ImpUtils.open(path);
 		for (ImagePlus view : MultiDThreePanes.getZYXZ(imp, 20)) {
 			view.show();
 		}

src/main/java/sc/fiji/snt/plugin/SkeletonConverterCmd.java

@@ -22,7 +22,6 @@
 
 package sc.fiji.snt.plugin;
 
-import ij.IJ;
 import ij.ImagePlus;
 import ij.gui.Roi;
 import net.imagej.ImageJ;
@@ -46,6 +45,7 @@
 import sc.fiji.snt.gui.GuiUtils;
 import sc.fiji.snt.gui.cmds.ChooseDatasetCmd;
 import sc.fiji.snt.gui.cmds.CommonDynamicCmd;
+import sc.fiji.snt.util.ImpUtils;
 import sc.fiji.snt.util.SNTColor;
 
 import java.io.File;
@@ -329,11 +329,11 @@ public void run() {
 					return;
 				}
 				SNTUtils.log("Loading " + maskImgFileChoice.getAbsolutePath());
-				chosenMaskImp = IJ.openImage(maskImgFileChoice.getAbsolutePath());
+				chosenMaskImp = ImpUtils.open(maskImgFileChoice);
 				ensureMaskImgVisibleOnAbort = true;
 				if (SNTUtils.fileAvailable(originalImgFileChoice)) {
 					SNTUtils.log("Loading " + originalImgFileChoice.getAbsolutePath());
-					chosenOrigImp = IJ.openImage(originalImgFileChoice.getAbsolutePath());
+					chosenOrigImp = ImpUtils.open(originalImgFileChoice);
 				} else {
 					isValidOrigImg = originalImgFileChoice == null || originalImgFileChoice.toString().isEmpty();
 				}

src/main/java/sc/fiji/snt/plugin/ij1/ShollAnalysisPlugin.java

@@ -51,6 +51,7 @@
 import sc.fiji.snt.gui.ShollAnalysisDialog;
 import sc.fiji.snt.gui.ShollAnalysisDialog.ShollPoint;
 import sc.fiji.snt.gui.ShollAnalysisDialog.ShollResults;
+import sc.fiji.snt.util.ImpUtils;
 import sc.fiji.snt.util.PointInImage;
 
 /**
@@ -105,7 +106,7 @@ public void run(final String ignoredArgument) {
 
 		if (!showDialog()) return;
 
-		imp = (impRequired) ? IJ.openImage(imgPath) : null;
+		imp = (impRequired) ? ImpUtils.open(imgPath) : null;
 		if (impRequired && imp == null || !validTracesFile(new File(tracesPath))) {
 			GuiUtils.errorPrompt("Invalid image or invalid Traces/(e)SWC file\n \n" +
 				imgPath + "\n" + tracesPath);

src/main/java/sc/fiji/snt/util/ImpUtils.java

@@ -120,10 +120,18 @@ public static ImagePlus open(final File file) {
 		return open(file, null);
 	}
 
+	public static ImagePlus open(final String filePathOrUrl) {
+		return open(filePathOrUrl, null);
+	}
+
 	public static ImagePlus open(final File file, final String title) {
+		return open(file.getAbsolutePath(), title);
+	}
+
+	public static ImagePlus open(final String filePathOrUrl, final String title) {
 		final boolean redirecting = IJ.redirectingErrorMessages();
 		IJ.redirectErrorMessages(true);
-		final ImagePlus imp = IJ.openImage(file.getAbsolutePath());
+		final ImagePlus imp = IJ.openImage(filePathOrUrl);
 		if (title != null)
 			imp.setTitle(title);
 		IJ.redirectErrorMessages(redirecting);
@@ -293,18 +301,16 @@ public static ImagePlus demo(final String img) {
 		} else if (nImg.contains("dda") || nImg.contains("c4") || nImg.contains("sholl")) {
 			return demoImageInternal("tests/ddaC.tif", "Drosophila_ddaC_Neuron.tif");
 		} else if (nImg.contains("op")) {
-			return ij.IJ.openImage(
-					"https://github.com/morphonets/SNT/raw/0b3451b8e62464a270c9aab372b4f651c4cf9af7/src/test/resources/OP_1.tif");
+			return open("https://github.com/morphonets/SNT/raw/0b3451b8e62464a270c9aab372b4f651c4cf9af7/src/test/resources/OP_1.tif", null);
 		} else if (nImg.equalsIgnoreCase("rat_hippocampal_neuron") || (nImg.contains("hip") && nImg.contains("multichannel"))) {
-			return ij.IJ.openImage("http://wsr.imagej.net/images/Rat_Hippocampal_Neuron.zip");
+			return open("http://wsr.imagej.net/images/Rat_Hippocampal_Neuron.zip", null);
 		} else if (nImg.contains("4d") || nImg.contains("701")) {
 			return cil701();
 		} else if (nImg.contains("multipolar") || nImg.contains("810")) {
 			return cil810();
 		} else if (nImg.contains("timelapse")) {
 			return (!nImg.contains("binary")) ? cil701()
-					: ij.IJ.openImage(
-							"https://github.com/morphonets/misc/raw/00369266e14f1a1ff333f99f0f72ef64077270da/dataset-demos/timelapse-binary-demo.zip");
+					: open("https://github.com/morphonets/misc/raw/00369266e14f1a1ff333f99f0f72ef64077270da/dataset-demos/timelapse-binary-demo.zip", null);
 		}
 		throw new IllegalArgumentException("Not a recognized demoImage argument: " + img);
 	}
@@ -354,7 +360,7 @@ private static ImagePlus cil810() {
 	}
 
 	private static ImagePlus cil701() {
-		final ImagePlus imp = IJ.openImage("https://cildata.crbs.ucsd.edu/media/images/701/701.tif");
+		final ImagePlus imp = open("https://cildata.crbs.ucsd.edu/media/images/701/701.tif", null);
 		if (imp != null) {
 			imp.setDimensions(1, 1, imp.getNSlices());
 			imp.getCalibration().setUnit("um");

src/main/java/sc/fiji/snt/viewer/Viewer3D.java

@@ -2341,7 +2341,7 @@ public boolean saveSnapshot() {
 				// HACK: current cartesian views may not reflect sensible 'anatomical views'.
 				// This is the case with the Allen CCF. While this is not addressed, we can
 				// just save a rotated copy of the snapshot. //TODO: Handle this more properly
-				final ij.ImagePlus imp = ij.IJ.openImage(file.getAbsolutePath());
+				final ij.ImagePlus imp = sc.fiji.snt.util.ImpUtils.open(file.getAbsolutePath());
 				if (imp != null) {
 					ij.IJ.run(imp, "Rotate 90 Degrees Left", "");
 					ij.IJ.saveAs(imp, "PNG", file.getAbsolutePath().replace(".png", "_rotated.png"));