Refactor properties v2 parser to use PropertiesSubset

The `PropertiesV1ConfigurationParser` uses the `PropertiesSubset` abstraction to pass subsets of properties between methods, while keeping track of the global name of each property.

We refactor the `PropertiesV2ConfigurationParser` to use the same abstraction, which allows us to eliminate many helper methods in `PropertiesUtils`.

Author: ppkarwasz

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/PropertiesUtils.java

@@ -16,33 +16,20 @@
  */
 package org.apache.logging.converter.config.internal;
 
-import java.util.Map;
+import java.util.Comparator;
 import java.util.Properties;
 import java.util.stream.Stream;
 import org.apache.logging.converter.config.ConfigurationConverterException;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.jspecify.annotations.Nullable;
 
 public final class PropertiesUtils {
 
-    public static @Nullable String getAndRemove(Properties properties, String key) {
-        return (String) properties.remove(key);
-    }
-
     public static String getLastComponent(String name) {
         int idx = name.lastIndexOf('.');
         return idx == -1 ? name : name.substring(idx + 1);
     }
 
-    public static Properties extractSubset(Properties properties, String prefix) {
-        Properties subset = org.apache.logging.log4j.util.PropertiesUtil.extractSubset(properties, prefix);
-        String value = getAndRemove(properties, prefix);
-        if (value != null) {
-            subset.setProperty("", value);
-        }
-        return subset;
-    }
-
     public static @Nullable String extractProperty(PropertiesSubset subset, String key) {
         return (String) subset.getProperties().remove(key);
     }
@@ -51,25 +38,24 @@ public static PropertiesSubset extractSubset(PropertiesSubset parentSubset, Stri
         Properties parentProperties = parentSubset.getProperties();
         Properties properties =
                 org.apache.logging.log4j.util.PropertiesUtil.extractSubset(parentProperties, childPrefix);
-        String value = getAndRemove(parentProperties, childPrefix);
+        String value = (String) parentProperties.remove(childPrefix);
         if (value != null) {
             properties.setProperty("", value);
         }
         return PropertiesSubset.of(addPrefixes(parentSubset.getPrefix(), childPrefix), properties);
     }
 
-    public static Map<String, Properties> partitionOnCommonPrefixes(Properties properties) {
-        return org.apache.logging.log4j.util.PropertiesUtil.partitionOnCommonPrefixes(properties, true);
-    }
-
     public static Stream<PropertiesSubset> partitionOnCommonPrefixes(PropertiesSubset parentSubset) {
         String parentPrefix = parentSubset.getPrefix();
         String effectivePrefix = parentPrefix.isEmpty() ? parentPrefix : parentPrefix + ".";
-        return org.apache.logging.log4j.util.PropertiesUtil.partitionOnCommonPrefixes(
+        Stream<PropertiesSubset> partitioned = org.apache.logging.log4j.util.PropertiesUtil.partitionOnCommonPrefixes(
                         parentSubset.getProperties(), true)
                 .entrySet()
                 .stream()
-                .map(entry -> PropertiesSubset.of(effectivePrefix + entry.getKey(), entry.getValue()));
+                .map(entry -> PropertiesSubset.of(effectivePrefix + entry.getKey(), entry.getValue()))
+                .sorted(Comparator.comparing(PropertiesSubset::getPrefix));
+        parentSubset.getProperties().clear();
+        return partitioned;
     }
 
     private static String addPrefixes(String left, String right) {
@@ -94,5 +80,19 @@ public static void throwIfNotEmpty(PropertiesSubset subset) {
         }
     }
 
+    /**
+     * @return {@code true} if the subset contains no properties.
+     */
+    public static boolean isEmpty(PropertiesSubset subset) {
+        return subset.getProperties().isEmpty();
+    }
+
+    /**
+     * @return {@code true} if the subset contains some properties.
+     */
+    public static boolean isNotEmpty(PropertiesSubset subset) {
+        return !isEmpty(subset);
+    }
+
     private PropertiesUtils() {}
 }

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/AbstractComponentParser.java

@@ -32,9 +32,9 @@
 import org.apache.logging.converter.config.internal.StringUtils;
 import org.apache.logging.converter.config.internal.XmlUtils;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ComponentParser;
 import org.apache.logging.converter.config.spi.v1.Log4j1ParserContext;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/PropertiesV1ConfigurationParser.java

@@ -35,7 +35,7 @@
 import org.apache.logging.converter.config.internal.PropertiesUtils;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
 import org.apache.logging.converter.config.spi.ConfigurationParser;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 
 @ServiceProvider(value = ConfigurationParser.class, resolution = Resolution.MANDATORY)
 public class PropertiesV1ConfigurationParser extends AbstractV1ConfigurationParser {

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/appender/AbstractAppenderParser.java

@@ -27,8 +27,8 @@
 import org.apache.logging.converter.config.internal.PropertiesUtils;
 import org.apache.logging.converter.config.internal.v1.AbstractComponentParser;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ParserContext;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.jspecify.annotations.Nullable;
 import org.w3c.dom.Element;
 

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/filter/DenyAllFilterParser.java

@@ -24,8 +24,8 @@
 import org.apache.logging.converter.config.internal.ComponentUtils;
 import org.apache.logging.converter.config.internal.v1.AbstractComponentParser;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ComponentParser;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.w3c.dom.Element;
 
 /**

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/filter/LevelMatchFilterParser.java

@@ -25,8 +25,8 @@
 import org.apache.logging.converter.config.internal.ComponentUtils;
 import org.apache.logging.converter.config.internal.ComponentUtils.ConfigurationNodeBuilder;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ComponentParser;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.w3c.dom.Element;
 
 /**

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/filter/LevelRangeFilterParser.java

@@ -25,8 +25,8 @@
 import org.apache.logging.converter.config.internal.ComponentUtils;
 import org.apache.logging.converter.config.internal.ComponentUtils.ConfigurationNodeBuilder;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ComponentParser;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.w3c.dom.Element;
 
 /**

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/filter/StringMatchFilterParser.java

@@ -26,8 +26,8 @@
 import org.apache.logging.converter.config.internal.ComponentUtils;
 import org.apache.logging.converter.config.internal.ComponentUtils.ConfigurationNodeBuilder;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ComponentParser;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.jspecify.annotations.Nullable;
 import org.w3c.dom.Element;
 

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/layout/EnhancedPatternLayoutParser.java

@@ -20,8 +20,8 @@
 import java.lang.invoke.MethodHandle;
 import java.util.Map;
 import org.apache.logging.converter.config.internal.v1.AbstractComponentParser;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ComponentParser;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.w3c.dom.Element;
 
 /**

log4j-converter-config/src/main/java/org/apache/logging/converter/config/internal/v1/layout/HtmlLayoutParser.java

@@ -24,8 +24,8 @@
 import org.apache.logging.converter.config.internal.StringUtils;
 import org.apache.logging.converter.config.internal.v1.AbstractComponentParser;
 import org.apache.logging.converter.config.spi.ConfigurationNode;
+import org.apache.logging.converter.config.spi.PropertiesSubset;
 import org.apache.logging.converter.config.spi.v1.Log4j1ComponentParser;
-import org.apache.logging.converter.config.spi.v1.PropertiesSubset;
 import org.w3c.dom.Element;
 
 /**