Module openj9.dtfj

Class DTFJJavaClass

java.lang.Object
com.ibm.j9ddr.vm29.view.dtfj.java.DTFJJavaClass
All Implemented Interfaces:
JavaClass

public class DTFJJavaClass extends Object implements JavaClass
  • Constructor Details

    • DTFJJavaClass

      public DTFJJavaClass(com.ibm.j9ddr.vm29.pointer.generated.J9ClassPointer j9class)
  • Method Details

    • getClassLoader

      public JavaClassLoader getClassLoader() throws CorruptDataException
      Description copied from interface: JavaClass
      Fetch the class loader associated with this class. Classes defined in the bootstrap class loader (including classes representing primitive types or void) will always return a JavaClassLoader representing the bootstrap class loader. This asymmetry with java.lang.Class#getClassLoader() is intentional.
      Specified by:
      getClassLoader in interface JavaClass
      Returns:
      the JavaClassLoader in which this class was defined
      Throws:
      CorruptDataException - if the class loader for this class cannot be found (a class cannot exist without a loader so this implies corruption)
    • getComponentType

      public JavaClass getComponentType() throws CorruptDataException
      Description copied from interface: JavaClass
      For array classes, returns a JavaClass representing the component type of this array class.
      Specified by:
      getComponentType in interface JavaClass
      Returns:
      a JavaClass representing the component type of this array class
      Throws:
      CorruptDataException
    • getConstantPoolReferences

      public Iterator getConstantPoolReferences()
      Description copied from interface: JavaClass
      Java classes may refer to other classes and to String objects via the class's constant pool. These references are followed by the garbage collector, forming edges on the graph of reachable objects. This getConstantPoolReferences() may be used to determine which objects are referred to by the receiver's constant pool.

      Although Java VMs typically permit only Class and String objects in the constant pool, some esoteric or future virtual machines may permit other types of objects to occur in the constant pool. This API imposes no restrictions on the types of JavaObjects which might be included in the Iterator.

      No assumption should be made about the order in which constant pool references are returned.

      Classes may also refer to objects through static variables. These may be found with the getDeclaredFields() API. Objects referenced by static variables are not returned by getConstantPoolReferences() unless the object is also referenced by the constant pool.

      Specified by:
      getConstantPoolReferences in interface JavaClass
      Returns:
      an iterator over the collection of JavaObjects which are referred to by the constant pool of this class
      See Also:
    • getDeclaredFields

      public Iterator getDeclaredFields()
      Description copied from interface: JavaClass
      Get the set of fields declared in this class.
      Specified by:
      getDeclaredFields in interface JavaClass
      Returns:
      an iterator over the collection of fields declared in this class.
      See Also:
    • getDeclaredMethods

      public Iterator getDeclaredMethods()
      Description copied from interface: JavaClass
      Get the set of methods declared in this class.
      Specified by:
      getDeclaredMethods in interface JavaClass
      Returns:
      an iterator over the collection of methods declared in this class.
      See Also:
    • getID

      public ImagePointer getID()
      Description copied from interface: JavaClass
      The ID of a class is a pointer to a section of memory which identifies the class. The contents of this memory are implementation defined.

      In some implementations getID() and getObject().getID() may return the same value. This implies that the class object is also the primary internal representation of the class. DTFJ users should not rely on this behaviour.

      In some implementations, getID() may return null for some classes. This indicates that the class is a synthetic class which has been constructed for DTFJ purposes only. The class has no physical representation in the VM.

      Specified by:
      getID in interface JavaClass
      Returns:
      a pointer to the class
    • getInterfaces

      public Iterator getInterfaces()
      Description copied from interface: JavaClass
      Get the set of names of interfaces directly implemented by this class.
      Specified by:
      getInterfaces in interface JavaClass
      Returns:
      an iterator over the collection of the names of interfaces directly implemented by this class. Some JVM implementations may choose to load interfaces lazily, so only the names are returned. The JavaClass objects may be found through the defining class loader.
      See Also:
    • getModifiers

      public int getModifiers() throws CorruptDataException
      Description copied from interface: JavaClass
      Return the Java language modifiers for this class.

      The modifiers are defined by the JVM Specification.

      Return MODIFIERS_UNAVAILABLE if the modifiers are unavailable. This might be the case if DTFJ is operating against an artefact such as a portable heap dump that does not contain information about a class's modifiers.

      Note that, for inner classes, the actual modifiers are returned, not the synthetic modifiers. For instance, a class will never have its 'protected' modifier set, even if the inner class was a protected member, since 'protected' is not a legal modifier for a class file.

      Specified by:
      getModifiers in interface JavaClass
      Returns:
      the modifiers for this class
      Throws:
      CorruptDataException
    • getName

      public String getName() throws CorruptDataException
      Description copied from interface: JavaClass
      Get the name of the class.
      Specified by:
      getName in interface JavaClass
      Returns:
      the name of the class in the form: "full/package/class$innerclass"
      Throws:
      CorruptDataException
    • getObject

      public JavaObject getObject() throws CorruptDataException
      Description copied from interface: JavaClass
      Fetch the java.lang.Class object associated with this class.

      In some implementations this may be null if no object has been created to represent this class, or if the class is synthetic.

      Specified by:
      getObject in interface JavaClass
      Returns:
      the java.lang.Class object associated with this class
      Throws:
      CorruptDataException
      See Also:
    • getReferences

      public Iterator getReferences()
      Description copied from interface: JavaClass
      Get the set of references from this class.
      Specified by:
      getReferences in interface JavaClass
      Returns:
      an iterator of JavaReferences
      See Also:
    • getSuperclass

      public JavaClass getSuperclass() throws CorruptDataException
      Description copied from interface: JavaClass
      Get the immediate superclass of this class.
      Specified by:
      getSuperclass in interface JavaClass
      Returns:
      the immediate superclass of this class, or null if this class has no superclass. For interfaces, Object, primitive types and void null is always returned.
      Throws:
      CorruptDataException
    • isArray

      public boolean isArray() throws CorruptDataException
      Description copied from interface: JavaClass
      Is this an array class ?
      Specified by:
      isArray in interface JavaClass
      Returns:
      true if this class is an array class
      Throws:
      CorruptDataException
    • equals

      public boolean equals(Object obj)
      Description copied from class: java.lang.Object
      Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison. The implementation in Object answers true only if the argument is the exact same object as the receiver (==).
      Specified by:
      equals in interface JavaClass
      Overrides:
      equals in class Object
      Parameters:
      obj - Object the object to compare with this object.
      Returns:
      boolean true if the object is the same as this object false if it is different from this object.
      See Also:
    • hashCode

      public int hashCode()
      Description copied from class: java.lang.Object
      Answers an integer hash code for the receiver. Any two objects which answer true when passed to .equals must answer the same value for this method.
      Specified by:
      hashCode in interface JavaClass
      Overrides:
      hashCode in class Object
      Returns:
      the receiver's hash.
      See Also:
    • getFilename

      public String getFilename() throws CorruptDataException
      Throws:
      CorruptDataException
    • getInstanceSize

      public long getInstanceSize() throws CorruptDataException
      Description copied from interface: JavaClass
      Returns the size in bytes of an instance of this class on the heap.

      The call is only meaningful for a non-array JavaClass, where all instances of the class are of the same size. If this method is called on a JavaArrayClass, where instances can be of different sizes, an UnsupportedOperationException will be thrown. DataUnavailable can be thrown if no value is available: for example when DTFJ is examining a javacore, where the instance size for a class is not recorded.

      Specified by:
      getInstanceSize in interface JavaClass
      Returns:
      size in bytes of an instance
      Throws:
      CorruptDataException
    • getProtectionDomain

      public JavaObject getProtectionDomain() throws DataUnavailable, CorruptDataException
      Description copied from interface: JavaClass
      Returns the protection domain for this class.
      Specified by:
      getProtectionDomain in interface JavaClass
      Returns:
      the protection domain or null for the default protection domain
      Throws:
      DataUnavailable
      CorruptDataException
    • isPacked

      public boolean isPacked()
    • getPackedDataSize

      public long getPackedDataSize() throws DataUnavailable, CorruptDataException
      Throws:
      DataUnavailable
      CorruptDataException