[MNG-7830] Switch from plexus-xml to stax / woodstox (#274)

diff --git a/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng1803PomValidationErrorIncludesLineNumberTest.java b/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng1803PomValidationErrorIncludesLineNumberTest.java
index 842eb99..7f16603 100644
--- a/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng1803PomValidationErrorIncludesLineNumberTest.java
+++ b/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng1803PomValidationErrorIncludesLineNumberTest.java
@@ -21,6 +21,7 @@
 import java.io.File;
 import java.util.List;
 
+import org.apache.maven.artifact.versioning.DefaultArtifactVersion;
 import org.apache.maven.shared.verifier.Verifier;
 import org.apache.maven.shared.verifier.util.ResourceExtractor;
 import org.junit.jupiter.api.Test;
@@ -59,8 +60,13 @@
         List<String> lines = verifier.loadLines(verifier.getLogFileName(), null);
         for (String line : lines) {
             if (line.contains(":bad/id:")) {
-                assertTrue("Line number not found in: " + line, line.indexOf("34") > 0);
-                assertTrue("Column number not found in: " + line, line.indexOf("19") > 0);
+                String location;
+                if (getMavenVersion().compareTo(new DefaultArtifactVersion("4.0.0-alpha-8-SNAPSHOT")) >= 0) {
+                    location = "line 34, column 7";
+                } else {
+                    location = "line 34, column 19";
+                }
+                assertTrue("Position not found in: " + line, line.indexOf(location) > 0);
                 foundError = true;
                 break;
             }
diff --git a/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng3748BadSettingsXmlTest.java b/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng3748BadSettingsXmlTest.java
index 39aa2c4..bf1ffec 100644
--- a/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng3748BadSettingsXmlTest.java
+++ b/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng3748BadSettingsXmlTest.java
@@ -68,10 +68,15 @@
 
             List<String> lines = verifier.loadLines(verifier.getLogFileName(), null);
             boolean foundWarning = false;
+            boolean isWarning = false;
             for (String line : lines) {
-                if (line.matches("(?i)\\[WARNING\\].*unrecognised tag.+unknown.+2.*")) {
-                    foundWarning = true;
-                    break;
+                if (!isWarning) {
+                    isWarning = line.startsWith("[WARNING]");
+                } else {
+                    if (line.matches("(?i).*unrecognised tag.+unknown.+2.*")) {
+                        foundWarning = true;
+                        break;
+                    }
                 }
             }
             assertTrue(foundWarning);
diff --git a/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng5576CdFriendlyVersions.java b/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng5576CdFriendlyVersions.java
index c456842..61c1bf4 100644
--- a/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng5576CdFriendlyVersions.java
+++ b/core-it-suite/src/test/java/org/apache/maven/it/MavenITmng5576CdFriendlyVersions.java
@@ -59,8 +59,12 @@
         assertEquals("1.0.0.changelist", props.getProperty("project.version"));
 
         List<String> lines = verifier.loadFile(new File(testDir, "log.txt"), false);
+        boolean seenScanning = false;
         for (String line : lines) {
-            assertFalse(line, line.contains("WARNING"));
+            seenScanning |= line.contains("Scanning for projects");
+            if (seenScanning) {
+                assertFalse(String.join("\n", lines), line.contains("WARNING"));
+            }
         }
     }
 
@@ -88,8 +92,12 @@
         assertEquals("1.0.0.changelist", props.getProperty("project.version"));
 
         List<String> lines = verifier.loadFile(new File(testDir, "log-bc.txt"), false);
+        boolean seenScanning = false;
         for (String line : lines) {
-            assertFalse(line, line.contains("WARNING"));
+            seenScanning |= line.contains("Scanning for projects");
+            if (seenScanning) {
+                assertFalse(String.join("\n", lines), line.contains("WARNING"));
+            }
         }
     }
 }
diff --git a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/parent.pom b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/parent.pom
index 46447bf..d557a66 100644
--- a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/parent.pom
+++ b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/parent.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <groupId>org.sonatype.mavenbook.multi</groupId>
diff --git a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-parent.pom b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-parent.pom
index b726198..88015cd 100644
--- a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-parent.pom
+++ b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-parent.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
diff --git a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-weather.pom b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-weather.pom
index 970ec47..0c1aedf 100644
--- a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-weather.pom
+++ b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-weather.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
diff --git a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-webapp.pom b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-webapp.pom
index 1ecae6d..680b417 100644
--- a/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-webapp.pom
+++ b/core-it-suite/src/test/resources/mng-6656-buildconsumer/expected/simple-webapp.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
diff --git a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/parent.pom b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/parent.pom
index 9291614..10700cb 100644
--- a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/parent.pom
+++ b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/parent.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <groupId>org.sonatype.mavenbook.multi</groupId>
diff --git a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-parent.pom b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-parent.pom
index cad5dee..1b15515 100644
--- a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-parent.pom
+++ b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-parent.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
diff --git a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-testutils.pom b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-testutils.pom
index 05580dc..d902a3c 100644
--- a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-testutils.pom
+++ b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-testutils.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
diff --git a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-weather.pom b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-weather.pom
index 43bfc9c..d4aa843 100644
--- a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-weather.pom
+++ b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-weather.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
diff --git a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-webapp.pom b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-webapp.pom
index a422ba0..9cc4868 100644
--- a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-webapp.pom
+++ b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/simple-webapp.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
diff --git a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/utils-parent.pom b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/utils-parent.pom
index a7fedb6..00f3624 100644
--- a/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/utils-parent.pom
+++ b/core-it-suite/src/test/resources/mng-6957-buildconsumer/expected/utils-parent.pom
@@ -1,5 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
 <!--
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
@@ -18,7 +17,6 @@
 specific language governing permissions and limitations
 under the License.
 -->
-
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>