src/java.base/share/classes/java/util/jar/JarFile.java

rev 15578 : 8165723: JarFile::isMultiRelease() method returns false when it should return true
Reviewed-by: alanb

@@ -834,34 +834,46 @@
 
     // Statics for hand-coded Boyer-Moore search
     private static final byte[] CLASSPATH_CHARS =
             {'C','L','A','S','S','-','P','A','T','H', ':', ' '};
 
-    // The bad character shift for "class-path:"
+    // The bad character shift for "class-path: "
     private static final byte[] CLASSPATH_LASTOCC;
 
+    // The good suffix shift for "class-path: "
+    private static final byte[] CLASSPATH_OPTOSFT;
+
     private static final byte[] MULTIRELEASE_CHARS =
             {'M','U','L','T','I','-','R','E','L','E', 'A', 'S', 'E', ':',
                     ' ', 'T', 'R', 'U', 'E'};
 
-    // The bad character shift for "multi-release: "
+    // The bad character shift for "multi-release: true"
     private static final byte[] MULTIRELEASE_LASTOCC;
 
+    // The good suffix shift for "multi-release: true"
+    private static final byte[] MULTIRELEASE_OPTOSFT;
+
     static {
         CLASSPATH_LASTOCC = new byte[64];
+        CLASSPATH_OPTOSFT = new byte[12];
         CLASSPATH_LASTOCC[(int)'C' - 32] = 1;
         CLASSPATH_LASTOCC[(int)'L' - 32] = 2;
         CLASSPATH_LASTOCC[(int)'S' - 32] = 5;
         CLASSPATH_LASTOCC[(int)'-' - 32] = 6;
         CLASSPATH_LASTOCC[(int)'P' - 32] = 7;
         CLASSPATH_LASTOCC[(int)'A' - 32] = 8;
         CLASSPATH_LASTOCC[(int)'T' - 32] = 9;
         CLASSPATH_LASTOCC[(int)'H' - 32] = 10;
         CLASSPATH_LASTOCC[(int)':' - 32] = 11;
         CLASSPATH_LASTOCC[(int)' ' - 32] = 12;
+        for (int i = 0; i < 11; i++) {
+            CLASSPATH_OPTOSFT[i] = 12;
+        }
+        CLASSPATH_OPTOSFT[11] = 1;
 
         MULTIRELEASE_LASTOCC = new byte[64];
+        MULTIRELEASE_OPTOSFT = new byte[19];
         MULTIRELEASE_LASTOCC[(int)'M' - 32] = 1;
         MULTIRELEASE_LASTOCC[(int)'I' - 32] = 5;
         MULTIRELEASE_LASTOCC[(int)'-' - 32] = 6;
         MULTIRELEASE_LASTOCC[(int)'L' - 32] = 9;
         MULTIRELEASE_LASTOCC[(int)'A' - 32] = 11;

@@ -870,10 +882,15 @@
         MULTIRELEASE_LASTOCC[(int)' ' - 32] = 15;
         MULTIRELEASE_LASTOCC[(int)'T' - 32] = 16;
         MULTIRELEASE_LASTOCC[(int)'R' - 32] = 17;
         MULTIRELEASE_LASTOCC[(int)'U' - 32] = 18;
         MULTIRELEASE_LASTOCC[(int)'E' - 32] = 19;
+        for (int i = 0; i < 17; i++) {
+            MULTIRELEASE_OPTOSFT[i] = 19;
+        }
+        MULTIRELEASE_OPTOSFT[17] = 6;
+        MULTIRELEASE_OPTOSFT[18] = 1;
     }
 
     private JarEntry getManEntry() {
         if (manEntry == null) {
             // First look up manifest entry using standard name

@@ -911,11 +928,11 @@
      * Returns true if the pattern {@code src} is found in {@code b}.
      * The {@code lastOcc} array is the precomputed bad character shifts.
      * Since there are no repeated substring in our search strings,
      * the good suffix shifts can be replaced with a comparison.
      */
-    private int match(byte[] src, byte[] b, byte[] lastOcc) {
+    private int match(byte[] src, byte[] b, byte[] lastOcc, byte[] optoSft) {
         int len = src.length;
         int last = b.length - len;
         int i = 0;
         next:
         while (i <= last) {

@@ -924,13 +941,12 @@
                 if (c >= ' ' && c <= 'z') {
                     if (c >= 'a') c -= 32; // Canonicalize
 
                     if (c != src[j]) {
                         // no match
-                        int goodShift = (j < len - 1) ? len : 1;
                         int badShift = lastOcc[c - 32];
-                        i += Math.max(j + 1 - badShift, goodShift);
+                        i += Math.max(j + 1 - badShift, optoSft[j]);
                         continue next;
                     }
                 } else {
                     // no match, character not valid for name
                     i += len;

@@ -956,14 +972,15 @@
             }
             JarEntry manEntry = getManEntry();
             if (manEntry != null) {
                 byte[] b = getBytes(manEntry);
                 hasClassPathAttribute = match(CLASSPATH_CHARS, b,
-                        CLASSPATH_LASTOCC) != -1;
+                        CLASSPATH_LASTOCC, CLASSPATH_OPTOSFT) != -1;
                 // is this a multi-release jar file
                 if (MULTI_RELEASE_ENABLED) {
-                    int i = match(MULTIRELEASE_CHARS, b, MULTIRELEASE_LASTOCC);
+                    int i = match(MULTIRELEASE_CHARS, b, MULTIRELEASE_LASTOCC,
+                            MULTIRELEASE_OPTOSFT);
                     if (i != -1) {
                         i += MULTIRELEASE_CHARS.length;
                         if (i < b.length) {
                             byte c = b[i++];
                             // Check that the value is followed by a newline