Removed unused code and some cleanups.

src/commonMain/kotlin/com/ashampoo/xmp/XMPPathFactory.kt

@@ -73,10 +73,10 @@ object XMPPathFactory {
     @kotlin.jvm.JvmStatic
     fun composeStructFieldPath(fieldNS: String, fieldName: String): String {
 
-        if (fieldNS.length == 0)
+        if (fieldNS.isEmpty())
             throw XMPException("Empty field namespace URI", XMPError.BADSCHEMA)
 
-        if (fieldName.length == 0)
+        if (fieldName.isEmpty())
             throw XMPException("Empty field name", XMPError.BADXPATH)
 
         val fieldPath = XMPPathParser.expandXPath(fieldNS, fieldName)
@@ -101,10 +101,10 @@ object XMPPathFactory {
     @kotlin.jvm.JvmStatic
     fun composeQualifierPath(qualNS: String, qualName: String): String {
 
-        if (qualNS.length == 0)
+        if (qualNS.isEmpty())
             throw XMPException("Empty qualifier namespace URI", XMPError.BADSCHEMA)
 
-        if (qualName.length == 0)
+        if (qualName.isEmpty())
             throw XMPException("Empty qualifier name", XMPError.BADXPATH)
 
         val qualPath = XMPPathParser.expandXPath(qualNS, qualName)

src/commonMain/kotlin/com/ashampoo/xmp/XMPUtils.kt

@@ -32,7 +32,7 @@ object XMPUtils {
     @kotlin.jvm.JvmStatic
     fun convertToBoolean(value: String?): Boolean {
 
-        if (value == null || value.length == 0)
+        if (value.isNullOrEmpty())
             throw XMPException("Empty convert-string", XMPError.BADVALUE)
 
         val valueLowercase = value.lowercase()
@@ -54,7 +54,7 @@ object XMPUtils {
     fun convertToInteger(rawValue: String?): Int {
         try {
 
-            if (rawValue == null || rawValue.length == 0)
+            if (rawValue.isNullOrEmpty())
                 throw XMPException("Empty convert-string", XMPError.BADVALUE)
 
             return if (rawValue.startsWith("0x"))
@@ -72,7 +72,7 @@ object XMPUtils {
 
         try {
 
-            if (rawValue == null || rawValue.length == 0)
+            if (rawValue.isNullOrEmpty())
                 throw XMPException("Empty convert-string", XMPError.BADVALUE)
 
             return if (rawValue.startsWith("0x"))
@@ -90,7 +90,7 @@ object XMPUtils {
 
         try {
 
-            if (rawValue == null || rawValue.length == 0)
+            if (rawValue.isNullOrEmpty())
                 throw XMPException("Empty convert-string", XMPError.BADVALUE)
 
             return rawValue.toDouble()

src/commonMain/kotlin/com/ashampoo/xmp/impl/QName.kt

@@ -46,6 +46,6 @@ class QName {
     }
 
     fun hasPrefix(): Boolean =
-        prefix != null && prefix!!.length > 0
+        prefix != null && prefix!!.isNotEmpty()
 
 }

src/commonMain/kotlin/com/ashampoo/xmp/impl/Utils.kt

@@ -188,7 +188,7 @@ object Utils {
      */
     fun isXMLName(name: String): Boolean {
 
-        if (name.length > 0 && !isNameStartChar(name[0]))
+        if (name.isNotEmpty() && !isNameStartChar(name[0]))
             return false
 
         for (i in 1 until name.length)
@@ -209,7 +209,7 @@ object Utils {
     @kotlin.jvm.JvmStatic
     fun isXMLNameNS(name: String): Boolean {
 
-        if (name.length > 0 && (!isNameStartChar(name[0]) || name[0] == ':'))
+        if (name.isNotEmpty() && (!isNameStartChar(name[0]) || name[0] == ':'))
             return false
 
         for (index in 1 until name.length)
@@ -257,9 +257,8 @@ object Utils {
         // slow path with escaping
         val buffer = StringBuilder(value.length * 4 / 3)
 
-        for (index in 0 until value.length) {
-
-            val char = value[index]
+        @Suppress("LoopWithTooManyJumpStatements")
+        for (char in value) {
 
             if (!(escapeWhitespaces && (char == '\t' || char == '\n' || char == '\r'))) {
 

src/commonMain/kotlin/com/ashampoo/xmp/impl/XMPIteratorImpl.kt

@@ -73,8 +73,8 @@ class XMPIteratorImpl(
         // the start node of the iteration depending on the schema and property filter
         var startNode: XMPNode? = null
         var initialPath: String? = null
-        val baseSchema = schemaNS != null && schemaNS.length > 0
-        val baseProperty = propPath != null && propPath.length > 0
+        val baseSchema = !schemaNS.isNullOrEmpty()
+        val baseProperty = !propPath.isNullOrEmpty()
 
         when {
 
@@ -344,7 +344,7 @@ class XMPIteratorImpl(
                 segmentName = currNode.name
             }
 
-            return if (parentPath == null || parentPath.length == 0) {
+            return if (parentPath.isNullOrEmpty()) {
 
                 segmentName
 
@@ -440,41 +440,34 @@ class XMPIteratorImpl(
          */
         override fun hasNext(): Boolean {
 
-            return if (returnProperty != null) {
-
-                // hasNext has been called before
-                true
-
-            } else if (skipSiblings) {
-
-                false
+            // hasNext has been called before
+            if (returnProperty != null)
+                return true
 
-            } else if (nodeChildrenIterator.hasNext()) {
+            if (skipSiblings)
+                return false
 
-                val child = nodeChildrenIterator.next()
+            if (!nodeChildrenIterator.hasNext())
+                return false
 
-                index++
+            val child = nodeChildrenIterator.next()
 
-                var path: String? = null
+            index++
 
-                if (child.options.isSchemaNode()) {
-                    baseNS = child.name
-                } else if (child.parent != null) {
-                    // for all but the root node and schema nodes
-                    path = accumulatePath(child, parentPath, index)
-                }
+            var path: String? = null
 
-                // report next property, skip not-leaf nodes in case options is set
-                if (!options.isJustLeafnodes() || !child.hasChildren()) {
-                    returnProperty = createPropertyInfo(child, baseNS!!, path!!)
-                    true
-                } else {
-                    hasNext()
-                }
+            if (child.options.isSchemaNode())
+                baseNS = child.name
+            else if (child.parent != null)
+                path = accumulatePath(child, parentPath, index)
 
-            } else {
-                false
+            // report next property, skip not-leaf nodes in case options is set
+            if (!options.isJustLeafnodes() || !child.hasChildren()) {
+                returnProperty = createPropertyInfo(child, baseNS!!, path!!)
+                return true
             }
+
+            return hasNext()
         }
     }
 

src/commonMain/kotlin/com/ashampoo/xmp/impl/XMPMetaImpl.kt

@@ -892,13 +892,14 @@ class XMPMetaImpl : XMPMeta {
 
         } else {
 
-            if (value != null && value.toString().length > 0)
+            if (value != null && value.toString().isNotEmpty())
                 throw XMPException("Composite nodes can't have values", XMPError.BADXPATH)
 
             // Can't change an array to a struct, or vice versa.
-            if (node.options.getOptions() and compositeMask != 0)
-                if (newOptions.getOptions() and compositeMask != node.options.getOptions() and compositeMask)
-                    throw XMPException("Requested and existing composite form mismatch", XMPError.BADXPATH)
+            if (node.options.getOptions() and compositeMask != 0 &&
+                newOptions.getOptions() and compositeMask != node.options.getOptions() and compositeMask
+            )
+                throw XMPException("Requested and existing composite form mismatch", XMPError.BADXPATH)
 
             node.removeChildren()
         }

src/commonMain/kotlin/com/ashampoo/xmp/impl/XMPNodeUtils.kt

@@ -79,7 +79,7 @@ object XMPNodeUtils {
 
             if (prefix == null) {
 
-                prefix = if (suggestedPrefix != null && suggestedPrefix.length != 0)
+                prefix = if (!suggestedPrefix.isNullOrEmpty())
                     schemaRegistry.registerNamespace(namespaceURI, suggestedPrefix)
                 else
                     throw XMPException("Unregistered schema namespace URI", XMPError.BADSCHEMA)
@@ -287,7 +287,7 @@ object XMPNodeUtils {
         if (options.isArrayOrdered())
             options.setArray(true)
 
-        if (options.isCompositeProperty() && itemValue != null && itemValue.toString().length > 0)
+        if (options.isCompositeProperty() && itemValue != null && itemValue.toString().isNotEmpty())
             throw XMPException("Structs and arrays can't have values", XMPError.BADOPTIONS)
 
         options.assertConsistency(options.getOptions())
@@ -417,16 +417,15 @@ object XMPNodeUtils {
      * @param segment     the segment containing the array index
      * @param createNodes flag if new nodes are allowed to be created.
      * @return Returns the index or index = -1 if not found
-     *
      */
     private fun findIndexedItem(arrayNode: XMPNode?, segment: String?, createNodes: Boolean): Int {
 
-        var segment = segment
         var index: Int
 
         try {
 
-            segment = segment!!.substring(1, segment.length - 1)
+            var segment = segment!!.substring(1, segment.length - 1)
+
             index = segment.toInt()
 
             if (index < 1)
@@ -471,6 +470,7 @@ object XMPNodeUtils {
             if (!currItem.options.isStruct())
                 throw XMPException("Field selector must be used on array of struct", XMPError.BADXPATH)
 
+            @Suppress("LoopWithTooManyJumpStatements")
             for (childIndex in 1..currItem.getChildrenLength()) {
 
                 val currField = currItem.getChild(childIndex)

src/commonMain/kotlin/com/ashampoo/xmp/impl/XMPNormalizer.kt

@@ -204,14 +204,14 @@ internal object XMPNormalizer {
 
                 val childValue = currChild.value
 
-                if (childValue == null || childValue.length == 0) {
+                if (childValue.isNullOrEmpty()) {
 
                     // Delete empty valued children that have no xml:lang.
                     it.remove()
 
                 } else {
 
-                    // Add an xml:lang qualifier with the value "x-repair".
+                    // Add a xml:lang qualifier with the value "x-repair".
                     val repairLang = XMPNode(XMPConst.XML_LANG, "x-repair")
                     currChild.addQualifier(repairLang)
                 }
@@ -220,7 +220,7 @@ internal object XMPNormalizer {
     }
 
     /**
-     * Visit all of the top level nodes looking for aliases. If there is
+     * Visit all the top level nodes looking for aliases. If there is
      * no base, transplant the alias subtree. If there is a base and strict
      * aliasing is on, make sure the alias and base subtrees match.
      *
@@ -427,7 +427,7 @@ internal object XMPNormalizer {
         if (!outerCall &&
             (
                 aliasNode.name != baseNode.name ||
-                    !aliasNode.options.equals(baseNode.options) ||
+                    aliasNode.options != baseNode.options ||
                     aliasNode.getQualifierLength() != baseNode.getQualifierLength()
                 )
         )

src/commonMain/kotlin/com/ashampoo/xmp/impl/XMPRDFParser.kt

@@ -226,7 +226,7 @@ internal object XMPRDFParser : XMPError {
                         // the XMP tree name if
                         // it doesn't have a name yet. Make sure this name matches
                         // the XMP tree name.
-                        if (xmpParent.name != null && xmpParent.name!!.length > 0) {
+                        if (xmpParent.name != null && xmpParent.name!!.isNotEmpty()) {
 
                             if (xmpParent.name != attribute.value)
                                 throw XMPException("Mismatched top level rdf:about values", XMPError.BADXMP)
@@ -1108,24 +1108,22 @@ internal object XMPRDFParser : XMPError {
      */
     private fun getRDFTermKind(node: Node): Int {
 
-        val nodeName = node.nodeName
-
         var namespace = when (node) {
             is Element -> node.namespaceURI
             is Attr -> node.namespaceURI
             else -> throw XMPException("Unknown Node ${node.nodeType}", XMPError.BADXMP)
         }
 
         if (namespace == null &&
-            ("about" == nodeName || "ID" == nodeName) &&
+            ("about" == node.nodeName || "ID" == node.nodeName) &&
             node is Attr && XMPConst.NS_RDF == node.ownerElement?.namespaceURI
         ) {
             namespace = XMPConst.NS_RDF
         }
 
         if (namespace == XMPConst.NS_RDF) {
 
-            when (nodeName) {
+            when (node.nodeName) {
 
                 "rdf:li" ->
                     return RDFTERM_LI

src/commonMain/kotlin/com/ashampoo/xmp/impl/xpath/XMPPathParser.kt

@@ -51,7 +51,7 @@ object XMPPathParser {
         pos.path = path
 
         // Pull out the first component and do some special processing on it: add the schema
-        // namespace prefix and and see if it is an alias. The start must be a "qualName".
+        // namespace prefix and see if it is an alias. The start must be a "qualName".
         parseRootNode(schemaNS, pos, expandedXPath)
 
         // Now continue to process the rest of the XMPPath string.
@@ -166,7 +166,7 @@ object XMPPathParser {
 
         pos.stepEnd++ // Look at the character after the leading '['.
 
-        if ('0' <= pos.path!![pos.stepEnd] && pos.path!![pos.stepEnd] <= '9') {
+        if (pos.path!![pos.stepEnd] in '0'..'9') {
 
             // A numeric (decimal integer) array index.
             while (
@@ -349,8 +349,8 @@ object XMPPathParser {
      */
     private fun verifyXPathRoot(schemaNS: String?, rootProp: String): String {
 
-        // Do some basic checks on the URI and name. Try to lookup the URI. See if the name is qualified.
-        if (schemaNS == null || schemaNS.length == 0)
+        // Do some basic checks on the URI and name. Try to look up the URI. See if the name is qualified.
+        if (schemaNS.isNullOrEmpty())
             throw XMPException("Schema namespace URI is required", XMPError.BADSCHEMA)
 
         if (rootProp[0] == '?' || rootProp[0] == '@')