class.java

gcc的组建

  public native Field getDeclaredField(String fieldName)
    throws NoSuchFieldException;

  /**
   * Get all the declared fields in this class, but not those inherited from
   * superclasses. This returns an array of length 0 if there are no fields,
   * including for primitive types. This does not return the implicit length
   * field of arrays. A security check may be performed, with
   * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as
   * <code>checkPackageAccess</code> both having to succeed.
   *
   * @return all declared fields in this class
   * @throws SecurityException if the security check fails
   * @since 1.1
   */
  public Field[] getDeclaredFields()
  {
    memberAccessCheck(Member.DECLARED);
    return getDeclaredFields(false);
  }

  native Field[] getDeclaredFields (boolean publicOnly);

  private native Method _getDeclaredMethod(String methodName, Class[] args);

  /**
   * Get a method declared in this class, where name is its simple name. The
   * implicit methods of Object are not available from arrays or interfaces.
   * Constructors (named "&lt;init&gt;" in the class file) and class initializers
   * (name "&lt;clinit&gt;") are not available.  The Virtual Machine allows
   * multiple methods with the same signature but differing return types; in
   * such a case the most specific return types are favored, then the final
   * choice is arbitrary. If the method takes no argument, an array of zero
   * elements and null are equivalent for the types argument. A security
   * check may be performed, with
   * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as
   * <code>checkPackageAccess</code> both having to succeed.
   *
   * @param methodName the name of the method
   * @param types the type of each parameter
   * @return the method
   * @throws NoSuchMethodException if the method does not exist
   * @throws SecurityException if the security check fails
   * @see #getDeclaredMethods()
   * @since 1.1
   */
  public Method getDeclaredMethod(String methodName, Class[] args)
    throws NoSuchMethodException
  {
    memberAccessCheck(Member.DECLARED);

    if ("<init>".equals(methodName) || "<clinit>".equals(methodName))
      throw new NoSuchMethodException(methodName);

    Method match = _getDeclaredMethod(methodName, args);
    if (match == null)
      throw new NoSuchMethodException(methodName);
    return match;
  }

  /**
   * Get all the declared methods in this class, but not those inherited from
   * superclasses. This returns an array of length 0 if there are no methods,
   * including for primitive types. This does include the implicit methods of
   * arrays and interfaces which mirror methods of Object, nor does it
   * include constructors or the class initialization methods. The Virtual
   * Machine allows multiple methods with the same signature but differing
   * return types; all such methods are in the returned array. A security
   * check may be performed, with
   * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as
   * <code>checkPackageAccess</code> both having to succeed.
   *
   * @return all declared methods in this class
   * @throws SecurityException if the security check fails
   * @since 1.1
   */
  public native Method[] getDeclaredMethods();
 
  /**
   * If this is a nested or inner class, return the class that declared it.
   * If not, return null.
   *
   * @return the declaring class of this class
   * @since 1.1
   */
  // This is marked as unimplemented in the JCL book.
  public native Class getDeclaringClass ();

  private native Field getField (String fieldName, int hash)
    throws NoSuchFieldException;

  /**
   * Get a public field declared or inherited in this class, where name is
   * its simple name. If the class contains multiple accessible fields by
   * that name, an arbitrary one is returned. The implicit length field of
   * arrays is not available. A security check may be performed, with
   * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as
   * <code>checkPackageAccess</code> both having to succeed.
   *
   * @param fieldName the name of the field
   * @return the field
   * @throws NoSuchFieldException if the field does not exist
   * @throws SecurityException if the security check fails
   * @see #getFields()
   * @since 1.1
   */
  public Field getField(String fieldName)
    throws NoSuchFieldException
  {
    memberAccessCheck(Member.PUBLIC);
    Field field = getField(fieldName, fieldName.hashCode());
    if (field == null)
      throw new NoSuchFieldException(fieldName);
    return field;
  }

  /**
   * Get all the public fields declared in this class or inherited from
   * superclasses. This returns an array of length 0 if there are no fields,
   * including for primitive types. This does not return the implicit length
   * field of arrays. A security check may be performed, with
   * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as
   * <code>checkPackageAccess</code> both having to succeed.
   *
   * @return all public fields in this class
   * @throws SecurityException if the security check fails
   * @since 1.1
   */
  public Field[] getFields()
  {
    memberAccessCheck(Member.PUBLIC);
    return internalGetFields();
  }

  /**
   * Like <code>getFields()</code> but without the security checks.
   */
  private Field[] internalGetFields()
  {
    HashSet set = new HashSet();
    set.addAll(Arrays.asList(getDeclaredFields(true)));
    Class[] interfaces = getInterfaces();
    for (int i = 0; i < interfaces.length; i++)
      set.addAll(Arrays.asList(interfaces[i].internalGetFields()));
    Class superClass = getSuperclass();
    if (superClass != null)
      set.addAll(Arrays.asList(superClass.internalGetFields()));
    return (Field[])set.toArray(new Field[set.size()]);
  }

  /**
   * Returns the <code>Package</code> in which this class is defined
   * Returns null when this information is not available from the
   * classloader of this class.
   *
   * @return the package for this class, if it is available
   * @since 1.2
   */
  public Package getPackage()
  {
    ClassLoader cl = getClassLoader();
    if (cl != null)
      return cl.getPackage(getPackagePortion(getName()));
    else
      return VMClassLoader.getPackage(getPackagePortion(getName()));
  }

  /**
   * Get the interfaces this class <em>directly</em> implements, in the
   * order that they were declared. This returns an empty array, not null,
   * for Object, primitives, void, and classes or interfaces with no direct
   * superinterface. Array types return Cloneable and Serializable.
   *
   * @return the interfaces this class directly implements
   */
  public native Class[] getInterfaces ();

  private final native void getSignature(StringBuffer buffer);
  private static final native String getSignature(Class[] args,
						  boolean is_construtor);

  public native Method _getMethod(String methodName, Class[] args);

  /**
   * Get a public method declared or inherited in this class, where name is
   * its simple name. The implicit methods of Object are not available from
   * interfaces.  Constructors (named "&lt;init&gt;" in the class file) and class
   * initializers (name "&lt;clinit&gt;") are not available.  The Virtual
   * Machine allows multiple methods with the same signature but differing
   * return types, and the class can inherit multiple methods of the same
   * return type; in such a case the most specific return types are favored,
   * then the final choice is arbitrary. If the method takes no argument, an
   * array of zero elements and null are equivalent for the types argument.
   * A security check may be performed, with
   * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as
   * <code>checkPackageAccess</code> both having to succeed.
   *
   * @param methodName the name of the method
   * @param types the type of each parameter
   * @return the method
   * @throws NoSuchMethodException if the method does not exist
   * @throws SecurityException if the security check fails
   * @see #getMethods()
   * @since 1.1
   */
  public Method getMethod(String methodName, Class[] args)
    throws NoSuchMethodException
  {
    memberAccessCheck(Member.PUBLIC);

    if ("<init>".equals(methodName) || "<clinit>".equals(methodName))
      throw new NoSuchMethodException(methodName);

    Method method = _getMethod(methodName, args);
    if (method == null)
      throw new NoSuchMethodException(methodName);
    return method;
  }

  private native int _getMethods (Method[] result, int offset);
  
  /**
   * Get all the public methods declared in this class or inherited from
   * superclasses. This returns an array of length 0 if there are no methods,
   * including for primitive types. This does not include the implicit
   * methods of interfaces which mirror methods of Object, nor does it
   * include constructors or the class initialization methods. The Virtual
   * Machine allows multiple methods with the same signature but differing
   * return types; all such methods are in the returned array. A security
   * check may be performed, with
   * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as
   * <code>checkPackageAccess</code> both having to succeed.
   *
   * @return all public methods in this class
   * @throws SecurityException if the security check fails
   * @since 1.1
   */
  public native Method[] getMethods();

  /**
   * Get the modifiers of this class.  These can be decoded using Modifier,
   * and is limited to one of public, protected, or private, and any of
   * final, static, abstract, or interface. An array class has the same
   * public, protected, or private modifier as its component type, and is
   * marked final but not an interface. Primitive types and void are marked
   * public and final, but not an interface.
   *
   * @return the modifiers of this class
   * @see Modifer
   * @since 1.1
   */
  public native int getModifiers ();
  
  /**
   * Get the name of this class, separated by dots for package separators.
   * If the class represents a primitive type, or void, then the
   * name of the type as it appears in the Java programming language
   * is returned.  For instance, <code>Byte.TYPE.getName()</code>
   * returns "byte".
   *
   * Arrays are specially encoded as shown on this table.
   * <pre>
   * array type          [<em>element type</em>
   *                     (note that the element type is encoded per
   *                      this table)
   * boolean             Z
   * byte                B
   * char                C
   * short               S
   * int                 I
   * long                J
   * float               F
   * double              D
   * void                V
   * class or interface, alone: &lt;dotted name&gt;
   * class or interface, as element type: L&lt;dotted name&gt;;
   * </pre>
   *
   * @return the name of this class
   */
  public native String getName ();

  /**
   * Get a resource URL using this class's package using the
   * getClassLoader().getResource() method.  If this class was loaded using
   * the system classloader, ClassLoader.getSystemResource() is used instead.
   *
   * <p>If the name you supply is absolute (it starts with a <code>/</code>),
   * then the leading <code>/</code> is removed and it is passed on to
   * getResource(). If it is relative, the package name is prepended, and
   * <code>.</code>'s are replaced with <code>/</code>.
   *
   * <p>The URL returned is system- and classloader-dependent, and could
   * change across implementations.
   *
   * @param resourceName the name of the resource, generally a path
   * @return the URL to the resource
   * @throws NullPointerException if name is null
   * @since 1.1
   */
  public URL getResource(String resourceName)
  {
    String name = resourcePath(resourceName);
    ClassLoader loader = getClassLoader();