--- a/jdk/src/java.base/share/classes/java/util/zip/ZipUtils.java	Tue Dec 08 12:05:51 2015 +0100
+++ b/jdk/src/java.base/share/classes/java/util/zip/ZipUtils.java	Tue Dec 08 09:25:01 2015 -0800
@@ -31,6 +31,8 @@
 import java.time.ZoneId;
 import java.util.concurrent.TimeUnit;
 
+import static java.util.zip.ZipConstants.ENDHDR;
+
 class ZipUtils {
 
     // used to adjust values between Windows and java epoch
@@ -133,7 +135,7 @@
      * The bytes are assumed to be in Intel (little-endian) byte order.
      */
     public static final int get16(byte b[], int off) {
-        return Byte.toUnsignedInt(b[off]) | (Byte.toUnsignedInt(b[off+1]) << 8);
+        return (b[off] & 0xff) | ((b[off + 1] & 0xff) << 8);
     }
 
     /**
@@ -160,4 +162,79 @@
     public static final int get32S(byte b[], int off) {
         return (get16(b, off) | (get16(b, off+2) << 16));
     }
+
+    // fields access methods
+    static final int CH(byte[] b, int n) {
+        return b[n] & 0xff ;
+    }
+
+    static final int SH(byte[] b, int n) {
+        return (b[n] & 0xff) | ((b[n + 1] & 0xff) << 8);
+    }
+
+    static final long LG(byte[] b, int n) {
+        return ((SH(b, n)) | (SH(b, n + 2) << 16)) & 0xffffffffL;
+    }
+
+    static final long LL(byte[] b, int n) {
+        return (LG(b, n)) | (LG(b, n + 4) << 32);
+    }
+
+    static final long GETSIG(byte[] b) {
+        return LG(b, 0);
+    }
+
+    // local file (LOC) header fields
+    static final long LOCSIG(byte[] b) { return LG(b, 0); } // signature
+    static final int  LOCVER(byte[] b) { return SH(b, 4); } // version needed to extract
+    static final int  LOCFLG(byte[] b) { return SH(b, 6); } // general purpose bit flags
+    static final int  LOCHOW(byte[] b) { return SH(b, 8); } // compression method
+    static final long LOCTIM(byte[] b) { return LG(b, 10);} // modification time
+    static final long LOCCRC(byte[] b) { return LG(b, 14);} // crc of uncompressed data
+    static final long LOCSIZ(byte[] b) { return LG(b, 18);} // compressed data size
+    static final long LOCLEN(byte[] b) { return LG(b, 22);} // uncompressed data size
+    static final int  LOCNAM(byte[] b) { return SH(b, 26);} // filename length
+    static final int  LOCEXT(byte[] b) { return SH(b, 28);} // extra field length
+
+    // extra local (EXT) header fields
+    static final long EXTCRC(byte[] b) { return LG(b, 4);}  // crc of uncompressed data
+    static final long EXTSIZ(byte[] b) { return LG(b, 8);}  // compressed size
+    static final long EXTLEN(byte[] b) { return LG(b, 12);} // uncompressed size
+
+    // end of central directory header (END) fields
+    static final int  ENDSUB(byte[] b) { return SH(b, 8); }  // number of entries on this disk
+    static final int  ENDTOT(byte[] b) { return SH(b, 10);}  // total number of entries
+    static final long ENDSIZ(byte[] b) { return LG(b, 12);}  // central directory size
+    static final long ENDOFF(byte[] b) { return LG(b, 16);}  // central directory offset
+    static final int  ENDCOM(byte[] b) { return SH(b, 20);}  // size of zip file comment
+    static final int  ENDCOM(byte[] b, int off) { return SH(b, off + 20);}
+
+    // zip64 end of central directory recoder fields
+    static final long ZIP64_ENDTOD(byte[] b) { return LL(b, 24);}  // total number of entries on disk
+    static final long ZIP64_ENDTOT(byte[] b) { return LL(b, 32);}  // total number of entries
+    static final long ZIP64_ENDSIZ(byte[] b) { return LL(b, 40);}  // central directory size
+    static final long ZIP64_ENDOFF(byte[] b) { return LL(b, 48);}  // central directory offset
+    static final long ZIP64_LOCOFF(byte[] b) { return LL(b, 8);}   // zip64 end offset
+
+    // central directory header (CEN) fields
+    static final long CENSIG(byte[] b, int pos) { return LG(b, pos + 0); }
+    static final int  CENVEM(byte[] b, int pos) { return SH(b, pos + 4); }
+    static final int  CENVER(byte[] b, int pos) { return SH(b, pos + 6); }
+    static final int  CENFLG(byte[] b, int pos) { return SH(b, pos + 8); }
+    static final int  CENHOW(byte[] b, int pos) { return SH(b, pos + 10);}
+    static final long CENTIM(byte[] b, int pos) { return LG(b, pos + 12);}
+    static final long CENCRC(byte[] b, int pos) { return LG(b, pos + 16);}
+    static final long CENSIZ(byte[] b, int pos) { return LG(b, pos + 20);}
+    static final long CENLEN(byte[] b, int pos) { return LG(b, pos + 24);}
+    static final int  CENNAM(byte[] b, int pos) { return SH(b, pos + 28);}
+    static final int  CENEXT(byte[] b, int pos) { return SH(b, pos + 30);}
+    static final int  CENCOM(byte[] b, int pos) { return SH(b, pos + 32);}
+    static final int  CENDSK(byte[] b, int pos) { return SH(b, pos + 34);}
+    static final int  CENATT(byte[] b, int pos) { return SH(b, pos + 36);}
+    static final long CENATX(byte[] b, int pos) { return LG(b, pos + 38);}
+    static final long CENOFF(byte[] b, int pos) { return LG(b, pos + 42);}
+
+    // The END header is followed by a variable length comment of size < 64k.
+    static final long END_MAXLEN = 0xFFFF + ENDHDR;
+    static final int READBLOCKSZ = 128;
 }