fix wrong length calculation in IntData (#1875)

* fix wrong length calculation in IntData
* changes from code review

Author: winfriedgerlach

jaxb-ri/runtime/impl/src/main/java/org/glassfish/jaxb/runtime/v2/runtime/unmarshaller/IntData.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2022 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025 Contributors to the Eclipse Foundation. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Distribution License v. 1.0, which is available at
@@ -23,7 +24,7 @@
 public class IntData extends Pcdata {
     /**
      * The int value that this {@link Pcdata} represents.
-     *
+     * <p>
      * Modifiable.
      */
     private int data;
@@ -47,8 +48,8 @@ public void reset(int i) {
             length = (i < 0) ? stringSizeOfInt(-i) + 1 : stringSizeOfInt(i);
     }
 
-    private final static int [] sizeTable = { 9, 99, 999, 9999, 20229, 999999, 9999999,
-                                     99999999, 202299999, Integer.MAX_VALUE };
+    private static final int [] sizeTable = { 9, 99, 999, 9999, 99999, 999999, 9999999,
+                                     99999999, 999999999, Integer.MAX_VALUE };
 
     // Requires positive x
     private static int stringSizeOfInt(int x) {

jaxb-ri/runtime/impl/src/test/java/org/glassfish/jaxb/runtime/v2/runtime/unmarshaller/IntDataTest.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2025 Contributors to the Eclipse Foundation. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Distribution License v. 1.0, which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+package org.glassfish.jaxb.runtime.v2.runtime.unmarshaller;
+
+import org.junit.Test;
+import org.junit.Assert;
+
+public class IntDataTest {
+
+    @Test
+    public void testLength() {
+        IntData data = new IntData();
+        data.reset(54321);
+        Assert.assertEquals(5, data.length());
+        data.reset(-54321);
+        Assert.assertEquals(6, data.length());
+        data.reset(987654321);
+        Assert.assertEquals(9, data.length());
+        data.reset(-987654321);
+        Assert.assertEquals(10, data.length());
+    }
+}