1 files changed, 40 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/session/cache/CacheNode.java b/src/main/java/org/traccar/session/cache/CacheNode.java
new file mode 100644
index 000000000..7b584f81a
--- /dev/null
+++ b/src/main/java/org/traccar/session/cache/CacheNode.java
@@ -0,0 +1,40 @@
+package org.traccar.session.cache;
+
+import org.traccar.model.BaseModel;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Stream;
+
+public class CacheNode {
+
+    private BaseModel value;
+
+    private final Map<Class<? extends BaseModel>, Set<CacheNode>> links = new HashMap<>();
+    private final Map<Class<? extends BaseModel>, Set<CacheNode>> backlinks = new HashMap<>();
+
+    public CacheNode(BaseModel value) {
+        this.value = value;
+    }
+
+    public BaseModel getValue() {
+        return value;
+    }
+
+    public void setValue(BaseModel value) {
+        this.value = value;
+    }
+
+    public Set<CacheNode> getLinks(Class<? extends BaseModel> clazz, boolean forward) {
+        var map = forward ? links : backlinks;
+        return map.computeIfAbsent(clazz, k -> new HashSet<>());
+    }
+
+    public Stream<CacheNode> getAllLinks(boolean forward) {
+        var map = forward ? links : backlinks;
+        return map.values().stream().flatMap(Set::stream);
+    }
+
+}