FileLocation: require non-Null arguments

Author: gab1one

src/main/java/org/scijava/io/location/FileLocation.java

@@ -37,6 +37,7 @@
 import java.net.URI;
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.Objects;
 import java.util.Set;
 
 /**
@@ -52,6 +53,7 @@ public class FileLocation extends AbstractLocation implements
 	private final File file;
 
 	public FileLocation(final File file) {
+		Objects.requireNonNull(file);
 		this.file = file;
 	}