Add safeguards for And/Or/Not pattern node types

Affects *PointCut, *TypePattern, *AnnotationTypePattern.

Relates to #215.

Signed-off-by: Alexander Kriegisch <Alexander@Kriegisch.name>

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/AndAnnotationTypePattern.java

@@ -130,8 +130,10 @@ public class AndAnnotationTypePattern extends AnnotationTypePattern {
 
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		left.traverse(visitor, ret);
-		right.traverse(visitor, ret);
+		if (this.left != null)
+			this.left.traverse(visitor, ret);
+		if (this.right != null)
+			this.right.traverse(visitor, ret);
 		return ret;
 	}
 

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/AndPointcut.java

@@ -131,8 +131,10 @@ public class AndPointcut extends Pointcut {
 
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		left.traverse(visitor, ret);
-		right.traverse(visitor, ret);
+		if (this.left != null)
+			this.left.traverse(visitor, ret);
+		if (this.right != null)
+			this.right.traverse(visitor, ret);
 		return ret;
 	}
 }

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/AndTypePattern.java

@@ -195,8 +195,10 @@ public class AndTypePattern extends TypePattern {
 	@Override
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		left.traverse(visitor, ret);
-		right.traverse(visitor, ret);
+		if (this.left != null)
+			this.left.traverse(visitor, ret);
+		if (this.right != null)
+			this.right.traverse(visitor, ret);
 		return ret;
 	}
 

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/NotAnnotationTypePattern.java

@@ -126,7 +126,8 @@ public class NotAnnotationTypePattern extends AnnotationTypePattern {
 
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		negatedPattern.traverse(visitor, ret);
+		if (this.negatedPattern != null)
+			this.negatedPattern.traverse(visitor, ret);
 		return ret;
 	}
 

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/NotPointcut.java

@@ -133,7 +133,8 @@ public class NotPointcut extends Pointcut {
 	@Override
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		this.body.traverse(visitor, ret);
+		if (this.body != null)
+			this.body.traverse(visitor, ret);
 		return ret;
 	}
 

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/NotTypePattern.java

@@ -178,7 +178,8 @@ public class NotTypePattern extends TypePattern {
 	@Override
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		negatedPattern.traverse(visitor, ret);
+		if (this.negatedPattern != null)
+			this.negatedPattern.traverse(visitor, ret);
 		return ret;
 	}
 

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/OrAnnotationTypePattern.java

@@ -69,8 +69,10 @@ public class OrAnnotationTypePattern extends AnnotationTypePattern {
 
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		left.traverse(visitor, ret);
-		right.traverse(visitor, ret);
+		if (this.left != null)
+			this.left.traverse(visitor, ret);
+		if (this.right != null)
+			this.right.traverse(visitor, ret);
 		return ret;
 	}
 

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/OrPointcut.java

@@ -139,8 +139,10 @@ public class OrPointcut extends Pointcut {
 
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		left.traverse(visitor, ret);
-		right.traverse(visitor, ret);
+		if (this.left != null)
+			this.left.traverse(visitor, ret);
+		if (this.right != null)
+			this.right.traverse(visitor, ret);
 		return ret;
 	}
 }

org.aspectj.matcher/src/main/java/org/aspectj/weaver/patterns/OrTypePattern.java

@@ -190,8 +190,10 @@ public class OrTypePattern extends TypePattern {
 
 	public Object traverse(PatternNodeVisitor visitor, Object data) {
 		Object ret = accept(visitor, data);
-		left.traverse(visitor, ret);
-		right.traverse(visitor, ret);
+		if (this.left != null)
+			this.left.traverse(visitor, ret);
+		if (this.right != null)
+			this.right.traverse(visitor, ret);
 		return ret;
 	}