MoreThanOneOkHttpClientDetector-6.kt

override fun isCallGraphRequired(): Boolean {
    return true
}

// Another call graph example: https://groups.google.com/forum/#!searchin/lint-dev/caller|sort:date/lint-dev/wFvCZOt4wZ8/g5punP99BAAJ
override fun analyzeCallGraph(context: Context, callGraph: CallGraphResult) {
    val contextualCallGraph = callGraph.callGraph.buildContextualCallGraph(callGraph.receiverEval)
    val okHttpClientNodes = contextualCallGraph.contextualNodes.stream().filter { contextualNode ->
        val element = contextualNode.node.target.element
        if(element is UMethod) {
            element.containingClass?.qualifiedName == OKHTTP_CLIENT && element.name == "OkHttpClient"
        } else {
            false
        }
    }.collect(Collectors.toList())
    if(okHttpClientNodes.size == 0) {
        // OkHttpClient not used in this project
        return
    }
    if(okHttpClientNodes.size != 1) {
        val parser = context.client.getUastParser(context.project)
        val node = okHttpClientNodes.first()
        val location = parser.createLocation(node.node.target.element)
        reportUsage(context, location)
        return
    }
    backwardSearch(context, callGraph.callGraph, contextualCallGraph, okHttpClientNodes.first())
}

private fun backwardSearch(context: Context, callGraph: CallGraph, contextualCallGraph: ContextualCallGraph, node: ContextualNode) {
    val callers = contextualCallGraph.inEdges(node)
    if(callers.isEmpty()) {
        // We are done
        return
    }
    if(callers.size == 1) {
        backwardSearch(context, callGraph, contextualCallGraph, callers.first().contextualNode)
        return
    }
    val parser = context.client.getUastParser(context.project)
    callers.map { it.contextualNode }.forEach { contextualNode ->
        val location = parser.createLocation(contextualNode.node.target.element)
        reportUsage(context, location)
    }
}