Package com.tonic.analysis.fingerprint.features

Class Level0Features

  • All Implemented Interfaces:
    FeatureVector
    public class Level0Features
extends Object
implements FeatureVector
    Ultra-stable fingerprint features: normalized signature shape plus called, accessed, and instantiated targets.

    • Constructor Detail

      • Level0Features

        public Level0Features​(String returnType,
                      int parameterCount,
                      List<String> paramTypes,
                      int exceptionHandlerCount,
                      int monitorCount,
                      Set<String> externalCallTargets,
                      Set<String> fieldAccessTargets,
                      Set<String> instantiatedTypes)
        Creates a level-0 feature set, normalizing the types and copying the target sets in sorted order.
        Parameters:
        returnType - the return type descriptor
        parameterCount - the number of parameters
        paramTypes - the parameter type descriptors
        exceptionHandlerCount - the number of exception table entries
        monitorCount - the number of monitorenter/monitorexit instructions
        externalCallTargets - the called method references
        fieldAccessTargets - the accessed field references
        instantiatedTypes - the class names created with new

    • Method Detail

      • normalizeType

        public static String normalizeType​(String desc)
        Collapses a type descriptor into a coarse category: O for objects, P for primitives, V for void, with one A per array dimension prefixed.
        Parameters:
        desc - the type descriptor; null or empty is treated as void
        Returns:
        the category string

      • computeHash

        public byte[] computeHash()
        Description copied from interface: FeatureVector
        Digests every extracted feature into a hash usable for equality and lookup.
        Specified by:
        computeHash in interface FeatureVector
        Returns:
        the digest bytes

      • isValid

        public boolean isValid()
        Specified by:
        isValid in interface FeatureVector
        Returns:
        true if extraction produced features that can be matched against

      • similarity

        public double similarity​(Level0Features other)
        Scores similarity to another level-0 feature set as a weighted mix of exact matches and Jaccard overlaps.
        Parameters:
        other - the feature set to compare against
        Returns:
        a score in [0, 1], 0 if other is null

      • getReturnTypeCategory

        public String getReturnTypeCategory()
        Returns:
        the return type category

      • getParameterCount

        public int getParameterCount()
        Returns:
        the parameter count

      • getSortedParamCategories

        public List<String> getSortedParamCategories()
        Returns:
        an unmodifiable view of the normalized parameter categories, sorted

      • getExceptionHandlerCount

        public int getExceptionHandlerCount()
        Returns:
        the exception handler count

      • getMonitorCount

        public int getMonitorCount()
        Returns:
        the monitor count

      • getExternalCallTargets

        public Set<String> getExternalCallTargets()
        Returns:
        an unmodifiable view of the called method references

      • getFieldAccessTargets

        public Set<String> getFieldAccessTargets()
        Returns:
        an unmodifiable view of the accessed field references

      • getInstantiatedTypes

        public Set<String> getInstantiatedTypes()
        Returns:
        an unmodifiable view of the instantiated class names