8267361: JavaTokenizer reads octal numbers mistakenly

src/jdk.compiler/share/classes/com/sun/tools/javac/parser/JavaTokenizer.java

@@ -640,6 +640,13 @@ private void scanNumber(int pos, int radix) {
                     break;
                 }
             }
+            // If it is not a floating point literal,
+            // the octal number should be rescanned correctly.
+            if (radix == 8) {
+                sb.setLength(0);
+                reset(pos);
+                scanDigits(pos, 8);
+            }
 
             if (acceptOneOf('l', 'L')) {
                 tk = TokenKind.LONGLITERAL;

test/langtools/tools/javac/lexer/OctalNumberTest.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8267361
+ * @summary JavaTokenizer reads octal numbers mistakenly
+ * @library /tools/lib
+ * @modules jdk.compiler/com.sun.tools.javac.api
+ *          jdk.compiler/com.sun.tools.javac.main
+ * @build toolbox.ToolBox toolbox.JavacTask
+ * @run main OctalNumberTest
+ */
+
+import java.util.Arrays;
+import java.util.List;
+
+import toolbox.JavacTask;
+import toolbox.ToolBox;
+import toolbox.TestRunner;
+import toolbox.Task;
+
+public class OctalNumberTest extends TestRunner {
+    ToolBox tb;
+
+    OctalNumberTest() {
+        super(System.err);
+        tb = new ToolBox();
+    }
+
+    public static void main(String[] args) throws Exception {
+        var t = new OctalNumberTest();
+        t.runTests();
+    }
+
+    @Test
+    public void testOctalNumber() throws Exception {
+        String code = """
+                class Digit {
+                    int a = 023; // normal
+                    int b = 089;
+                    int c = 02389;
+                    int d = 028a;
+                    int e = 02a8;
+                }""";
+        List<String> output = new JavacTask(tb)
+                .sources(code)
+                .options("-XDrawDiagnostics")
+                .run(Task.Expect.FAIL)
+                .writeAll()
+                .getOutputLines(Task.OutputKind.DIRECT);
+        List<String> expected = Arrays.asList(
+                "Digit.java:3:14: compiler.err.expected: ';'",
+                "Digit.java:4:16: compiler.err.expected: ';'",
+                "Digit.java:5:15: compiler.err.expected: ';'",
+                "Digit.java:5:17: compiler.err.expected: token.identifier",
+                "Digit.java:6:15: compiler.err.expected: ';'",
+                "Digit.java:6:17: compiler.err.expected: token.identifier",
+                "6 errors");
+        tb.checkEqual(expected, output);
+    }
+}