1 files changed, 84 insertions, 0 deletions
diff --git a/config-lib/src/main/java/com/yahoo/config/OptionalPathNode.java b/config-lib/src/main/java/com/yahoo/config/OptionalPathNode.java
new file mode 100644
index 00000000000..8a6414d798f
--- /dev/null
+++ b/config-lib/src/main/java/com/yahoo/config/OptionalPathNode.java
@@ -0,0 +1,84 @@
+// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config;
+
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+
+/**
+ * Represents a 'path' in a {@link ConfigInstance}, usually a filename, can be optional
+ *
+ * @author hmusum
+ */
+public class OptionalPathNode extends LeafNode<Optional<Path>> {
+
+    private final Optional<FileReference> fileReference;
+
+    public OptionalPathNode() {
+        fileReference = Optional.empty();
+    }
+
+    public OptionalPathNode(FileReference fileReference) {
+        super(true);
+        this.value = Optional.of(Path.of(fileReference.value()));
+        this.fileReference = Optional.of(fileReference);
+    }
+
+    public OptionalPathNode(Optional<FileReference> fileReference) {
+        super(true);
+        this.value = fileReference.map(reference -> Path.of(reference.value()));
+        this.fileReference = fileReference;
+    }
+
+    public Optional<Path> value() {
+        return value;
+    }
+
+    @Override
+    public String getValue() {
+        return value.toString();
+    }
+
+    @Override
+    public String toString() {
+        return (value.isEmpty()) ? "(empty)" : '"' + value.get().toString() + '"';
+    }
+
+    @Override
+    protected boolean doSetValue(String stringVal) {
+        throw new UnsupportedOperationException("doSetValue should not be necessary anymore!");
+    }
+
+    @Override
+    void serialize(String name, Serializer serializer) {
+        value.ifPresent(path -> serializer.serialize(name, path.toString()));
+    }
+
+    @Override
+    void serialize(Serializer serializer) {
+        value.ifPresent(path -> serializer.serialize(path.toString()));
+    }
+
+    public Optional<FileReference> getFileReference() {
+        return fileReference;
+    }
+
+    public static List<Optional<FileReference>> toFileReferences(List<OptionalPathNode> pathNodes) {
+        List<Optional<FileReference>> fileReferences = new ArrayList<>();
+        for (OptionalPathNode pathNode : pathNodes)
+            fileReferences.add(pathNode.getFileReference());
+        return fileReferences;
+    }
+
+    public static Map<String, Optional<FileReference>> toFileReferenceMap(Map<String, OptionalPathNode> map) {
+        Map<String, Optional<FileReference>> ret = new LinkedHashMap<>();
+        for (Map.Entry<String, OptionalPathNode> e : map.entrySet()) {
+            ret.put(e.getKey(), e.getValue().getFileReference());
+        }
+        return ret;
+    }
+
+}