src/java.base/share/classes/java/util/Properties.java

rev 16769 : 8176041: Optimize handling of comment lines in Properties$LineReader.readLine
Reviewed-by: shade

*** 492,503 ****
                      appendedLineBegin = false;
                  }
                  if (isNewLine) {
                      isNewLine = false;
                      if (c == '#' || c == '!') {
                          isCommentLine = true;
-                         continue;
                      }
                  }
  
                  if (c != '\n' && c != '\r') {
                      lineBuf[len++] = c;
--- 492,520 ----
                      appendedLineBegin = false;
                  }
                  if (isNewLine) {
                      isNewLine = false;
                      if (c == '#' || c == '!') {
+                         // Comment, quickly consume the rest of the line,
+                         // resume on line-break and backslash.
+                         if (inStream != null) {
+                             while (inOff < inLimit) {
+                                 byte b = inByteBuf[inOff++];
+                                 if (b == '\n' || b == '\r' || b == '\\') {
+                                     c = (char)(0xff & b);
+                                     break;
+                                 }
+                             }
+                         } else {
+                             while (inOff < inLimit) {
+                                 c = inCharBuf[inOff++];
+                                 if (c == '\n' || c == '\r' || c == '\\') {
+                                     break;
+                                 }
+                             }
+                         }
                          isCommentLine = true;
                      }
                  }
  
                  if (c != '\n' && c != '\r') {
                      lineBuf[len++] = c;