import java
import semmle.code.java.dataflow.DataFlow

module Config implements DataFlow::ConfigSig {
  predicate isSource(DataFlow::Node src) { src.asExpr() instanceof ClassInstanceExpr }

  predicate isSink(DataFlow::Node sink) {
    exists(MethodCall ma |
      ma.getMethod().hasName("sink") and
      ma.getAnArgument() = sink.asExpr()
    )
  }
}

module Flow = DataFlow::Global<Config>;

from DataFlow::Node src, DataFlow::Node sink
where Flow::flow(src, sink)
select src, sink