Refactor XxeQuery

Author: egregius313

java/ql/lib/semmle/code/java/security/XxeQuery.qll

@@ -1,7 +1,7 @@
 /** Provides default definitions to be used in XXE queries. */
 
 import java
-private import semmle.code.java.dataflow.TaintTracking2
+private import semmle.code.java.dataflow.TaintTracking
 private import semmle.code.java.security.XmlParsers
 import semmle.code.java.security.Xxe
 
@@ -11,7 +11,7 @@ import semmle.code.java.security.Xxe
  */
 private class DefaultXxeSink extends XxeSink {
   DefaultXxeSink() {
-    not exists(SafeSaxSourceFlowConfig safeSource | safeSource.hasFlowTo(this)) and
+    not SafeSaxSourceFlow::flowTo(this) and
     exists(XmlParserCall parse |
       parse.getSink() = this.asExpr() and
       not parse.isSafe()
@@ -22,14 +22,12 @@ private class DefaultXxeSink extends XxeSink {
 /**
  * A taint-tracking configuration for safe XML readers used to parse XML documents.
  */
-private class SafeSaxSourceFlowConfig extends TaintTracking2::Configuration {
-  SafeSaxSourceFlowConfig() { this = "SafeSaxSourceFlowConfig" }
+private module SafeSaxSourceFlowConfig implements DataFlow::ConfigSig {
+  predicate isSource(DataFlow::Node src) { src.asExpr() instanceof SafeSaxSource }
 
-  override predicate isSource(DataFlow::Node src) { src.asExpr() instanceof SafeSaxSource }
+  predicate isSink(DataFlow::Node sink) { sink.asExpr() = any(XmlParserCall parse).getSink() }
 
-  override predicate isSink(DataFlow::Node sink) {
-    sink.asExpr() = any(XmlParserCall parse).getSink()
-  }
-
-  override int fieldFlowBranchLimit() { result = 0 }
+  int fieldFlowBranchLimit() { result = 0 }
 }
+
+private module SafeSaxSourceFlow = TaintTracking::Global<SafeSaxSourceFlowConfig>;