// Create a Project.
import org.opalj.collection.immutable._; import org.opalj.br._ ; import org.opalj.br.analyses._
val p = Project(org.opalj.bytecode.RTJar)

// Get the methods which override a specific method, e.g., "java.lang.Object{ public String toString() }".
val toStringOverriders = p.overridingMethods(p.ObjectClassFile.get.findMethod("toString").head/*Object just defines one method named "toString"*/)
toStringOverriders.size
println(toStringOverriders.map(_.toJava).mkString("Methods overriding toString:\n\t","\n\t","\n"))


// The following counts the number of concrete "String toString()" methods in the project. 
// If the class hierarchy is complete this number should be equal to the number of methods 
// which override "java.lang.Object"'s toSring method.
import MethodDescriptor.JustReturnsString
p.allProjectClassFiles.map{cf => cf.methods.count(m => m.name == "toString" && m.isNotAbstract && m.descriptor == JustReturnsString)}.sum

// Example to get all methods which implement/override List's size method:
println(p.overridingMethods(p.classFile(ObjectType("java/util/List")).get.findMethod("size").head).map(m => m.toJava).toList.sorted.mkString("\n"))
// The result will, however, not include java/util/List's size method since the size method is abstract.