src/java.base/share/classes/jdk/internal/jrtfs/AbstractJrtPath.java

@@ -121,11 +121,12 @@
 
     @Override
     public final AbstractJrtPath getName(int index) {
         initOffsets();
         if (index < 0 || index >= offsets.length) {
-            throw new IllegalArgumentException();
+            throw new IllegalArgumentException("index: " +
+                index + ", offsets length: " + offsets.length);
         }
         int begin = offsets[index];
         int len;
         if (index == (offsets.length - 1)) {
             len = path.length - begin;

@@ -143,11 +144,12 @@
         initOffsets();
         if (beginIndex < 0
                 || beginIndex >= offsets.length
                 || endIndex > offsets.length
                 || beginIndex >= endIndex) {
-            throw new IllegalArgumentException();
+            throw new IllegalArgumentException("beginIndex: " + beginIndex +
+                ", endIndex: " + endIndex + ", offsets length: " + offsets.length);
         }
 
         // starting offset and length
         int begin = offsets[beginIndex];
         int len;

@@ -239,11 +241,11 @@
         final AbstractJrtPath o = checkPath(other);
         if (o.equals(this)) {
             return newJrtPath(new byte[0], true);
         }
         if (/* this.getFileSystem() != o.getFileSystem() || */this.isAbsolute() != o.isAbsolute()) {
-            throw new IllegalArgumentException();
+            throw new IllegalArgumentException("this.isAbsolute(): " + this.isAbsolute());
         }
         int mc = this.getNameCount();
         int oc = o.getNameCount();
         int n = Math.min(mc, oc);
         int i = 0;

@@ -309,11 +311,11 @@
     }
 
     @Override
     public final Path resolveSibling(Path other) {
         if (other == null) {
-            throw new NullPointerException();
+            throw new NullPointerException("other");
         }
         Path parent = getParent();
         return (parent == null) ? other : parent.resolve(other);
     }
 

@@ -394,14 +396,15 @@
         return newJrtPath(res, true);
     }
 
     private AbstractJrtPath checkPath(Path path) {
         if (path == null) {
-            throw new NullPointerException();
+            throw new NullPointerException("path");
         }
         if (!(path instanceof AbstractJrtPath)) {
-            throw new ProviderMismatchException();
+            throw new ProviderMismatchException("path class:" + 
+                path.getClass().getName());
         }
         return (AbstractJrtPath) path;
     }
 
     // create offset list if not already created

@@ -473,11 +476,11 @@
             if (c == (byte) '/' && prevC == '/') {
                 return normalize(path, i - 1);
             }
             if (c == '\u0000') {
                 throw new InvalidPathException(JrtFileSystem.getString(path),
-                        "Path: nul character not allowed");
+                        "Path: null character not allowed");
             }
             prevC = c;
         }
 
         if (path.length > 1 && path[path.length - 1] == '/') {