BUG-4456: add RecursiveExtensionResolver

[yangtools.git] / yang / yang-parser-impl / src / main / java / org / opendaylight / yangtools / yang / parser / stmt / rfc6020 / effective / ExtensionEffectiveStatementImpl.java

diff --git a/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/rfc6020/effective/ExtensionEffectiveStatementImpl.java b/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/rfc6020/effective/ExtensionEffectiveStatementImpl.java
index fd9623b0bc3f0c59a7f06a387e2f9e7ae3922f42..d40c8ea519ad1342c64ab11ce600baf548a214fa 100644 (file)
--- a/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/rfc6020/effective/ExtensionEffectiveStatementImpl.java
+++ b/yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/rfc6020/effective/ExtensionEffectiveStatementImpl.java
@@ -8,7 +8,9 @@
 package org.opendaylight.yangtools.yang.parser.stmt.rfc6020.effective;
 
 import com.google.common.collect.ImmutableList;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
+import java.util.Deque;
 import java.util.List;
 import java.util.Objects;
 import org.opendaylight.yangtools.yang.common.QName;
@@ -21,6 +23,40 @@ import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext;
 
 public class ExtensionEffectiveStatementImpl extends AbstractEffectiveDocumentedNode<QName, ExtensionStatement>
         implements ExtensionDefinition {
+    private static final class RecursionDetector extends ThreadLocal<Deque<ExtensionEffectiveStatementImpl>> {
+        boolean check(final ExtensionEffectiveStatementImpl current) {
+            final Deque<ExtensionEffectiveStatementImpl> stack = get();
+            if (stack != null) {
+                for (ExtensionEffectiveStatementImpl s : stack) {
+                    if (s == current) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        }
+
+        void push(final ExtensionEffectiveStatementImpl current) {
+            Deque<ExtensionEffectiveStatementImpl> stack = get();
+            if (stack == null) {
+                stack = new ArrayDeque<>(1);
+                set(stack);
+            }
+
+            stack.push(current);
+        }
+
+        void pop() {
+            Deque<ExtensionEffectiveStatementImpl> stack = get();
+            stack.pop();
+            if (stack.isEmpty()) {
+                remove();
+            }
+        }
+    }
+
+    private static final RecursionDetector TOSTRING_DETECTOR = new RecursionDetector();
+
     private final QName qname;
     private final String argument;
     private final SchemaPath schemaPath;
@@ -111,12 +147,30 @@ public class ExtensionEffectiveStatementImpl extends AbstractEffectiveDocumented
 
     @Override
     public String toString() {
+        if (TOSTRING_DETECTOR.check(this)) {
+            return recursedToString();
+        }
+
+        TOSTRING_DETECTOR.push(this);
+        try {
+            return ExtensionEffectiveStatementImpl.class.getSimpleName() + "[" +
+                    "argument=" + argument +
+                    ", qname=" + qname +
+                    ", schemaPath=" + schemaPath +
+                    ", extensionSchemaNodes=" + unknownNodes +
+                    ", yin=" + yin +
+                    "]";
+        } finally {
+            TOSTRING_DETECTOR.pop();
+        }
+    }
+
+    private String recursedToString() {
         return ExtensionEffectiveStatementImpl.class.getSimpleName() + "[" +
                 "argument=" + argument +
                 ", qname=" + qname +
                 ", schemaPath=" + schemaPath +
-                ", extensionSchemaNodes=" + unknownNodes +
                 ", yin=" + yin +
-                "]";
+                " <RECURSIVE> ]";
     }
 }