field.java

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     *              is inaccessible.
     * @exception IllegalArgumentException  if the specified object is not an
     *              instance of the class or interface declaring the underlying
     *              field (or a subclass or implementor thereof), 
     *              or if an unwrapping conversion fails.
     * @exception NullPointerException      if the specified object is null
     *              and the field is an instance field.
     * @exception ExceptionInInitializerError if the initialization provoked
     *              by this method fails.
     * @see       Field#set
     */
    public void setByte(Object obj, byte b)
	throws IllegalArgumentException, IllegalAccessException
    {
        getFieldAccessor(obj).setByte(obj, b);
    }

    /**
     * Sets the value of a field as a <code>char</code> on the specified object.
     * This method is equivalent to
     * <code>set(obj, cObj)</code>,
     * where <code>cObj</code> is a <code>Character</code> object and 
     * <code>cObj.charValue() == c</code>.
     *
     * @param obj the object whose field should be modified
     * @param c   the new value for the field of <code>obj</code>
     * being modified
     * 
     * @exception IllegalAccessException    if the underlying field
     *              is inaccessible.
     * @exception IllegalArgumentException  if the specified object is not an
     *              instance of the class or interface declaring the underlying
     *              field (or a subclass or implementor thereof), 
     *              or if an unwrapping conversion fails.
     * @exception NullPointerException      if the specified object is null
     *              and the field is an instance field.
     * @exception ExceptionInInitializerError if the initialization provoked
     *              by this method fails.
     * @see       Field#set
     */
    public void setChar(Object obj, char c)
	throws IllegalArgumentException, IllegalAccessException
    {
        getFieldAccessor(obj).setChar(obj, c);
    }

    /**
     * Sets the value of a field as a <code>short</code> on the specified object.
     * This method is equivalent to
     * <code>set(obj, sObj)</code>,
     * where <code>sObj</code> is a <code>Short</code> object and 
     * <code>sObj.shortValue() == s</code>.
     *
     * @param obj the object whose field should be modified
     * @param s   the new value for the field of <code>obj</code>
     * being modified
     * 
     * @exception IllegalAccessException    if the underlying field
     *              is inaccessible.
     * @exception IllegalArgumentException  if the specified object is not an
     *              instance of the class or interface declaring the underlying
     *              field (or a subclass or implementor thereof), 
     *              or if an unwrapping conversion fails.
     * @exception NullPointerException      if the specified object is null
     *              and the field is an instance field.
     * @exception ExceptionInInitializerError if the initialization provoked
     *              by this method fails.
     * @see       Field#set
     */
    public void setShort(Object obj, short s)
	throws IllegalArgumentException, IllegalAccessException
    {
        getFieldAccessor(obj).setShort(obj, s);
    }

    /**
     * Sets the value of a field as an <code>int</code> on the specified object.
     * This method is equivalent to
     * <code>set(obj, iObj)</code>,
     * where <code>iObj</code> is a <code>Integer</code> object and 
     * <code>iObj.intValue() == i</code>.
     *
     * @param obj the object whose field should be modified
     * @param i   the new value for the field of <code>obj</code>
     * being modified
     * 
     * @exception IllegalAccessException    if the underlying field
     *              is inaccessible.
     * @exception IllegalArgumentException  if the specified object is not an
     *              instance of the class or interface declaring the underlying
     *              field (or a subclass or implementor thereof), 
     *              or if an unwrapping conversion fails.
     * @exception NullPointerException      if the specified object is null
     *              and the field is an instance field.
     * @exception ExceptionInInitializerError if the initialization provoked
     *              by this method fails.
     * @see       Field#set
     */
    public void setInt(Object obj, int i)
	throws IllegalArgumentException, IllegalAccessException
    {
        getFieldAccessor(obj).setInt(obj, i);
    }

    /**
     * Sets the value of a field as a <code>long</code> on the specified object.
     * This method is equivalent to
     * <code>set(obj, lObj)</code>,
     * where <code>lObj</code> is a <code>Long</code> object and 
     * <code>lObj.longValue() == l</code>.
     *
     * @param obj the object whose field should be modified
     * @param l   the new value for the field of <code>obj</code>
     * being modified
     * 
     * @exception IllegalAccessException    if the underlying field
     *              is inaccessible.
     * @exception IllegalArgumentException  if the specified object is not an
     *              instance of the class or interface declaring the underlying
     *              field (or a subclass or implementor thereof), 
     *              or if an unwrapping conversion fails.
     * @exception NullPointerException      if the specified object is null
     *              and the field is an instance field.
     * @exception ExceptionInInitializerError if the initialization provoked
     *              by this method fails.
     * @see       Field#set
     */
    public void setLong(Object obj, long l)
	throws IllegalArgumentException, IllegalAccessException
    {
        getFieldAccessor(obj).setLong(obj, l);
    }

    /**
     * Sets the value of a field as a <code>float</code> on the specified object.
     * This method is equivalent to
     * <code>set(obj, fObj)</code>,
     * where <code>fObj</code> is a <code>Float</code> object and 
     * <code>fObj.floatValue() == f</code>.
     *
     * @param obj the object whose field should be modified
     * @param f   the new value for the field of <code>obj</code>
     * being modified
     * 
     * @exception IllegalAccessException    if the underlying field
     *              is inaccessible.
     * @exception IllegalArgumentException  if the specified object is not an
     *              instance of the class or interface declaring the underlying
     *              field (or a subclass or implementor thereof), 
     *              or if an unwrapping conversion fails.
     * @exception NullPointerException      if the specified object is null
     *              and the field is an instance field.
     * @exception ExceptionInInitializerError if the initialization provoked
     *              by this method fails.
     * @see       Field#set
     */
    public void setFloat(Object obj, float f)
	throws IllegalArgumentException, IllegalAccessException
    {
        getFieldAccessor(obj).setFloat(obj, f);
    }

    /**
     * Sets the value of a field as a <code>double</code> on the specified object.
     * This method is equivalent to
     * <code>set(obj, dObj)</code>,
     * where <code>dObj</code> is a <code>Double</code> object and 
     * <code>dObj.doubleValue() == d</code>.
     *
     * @param obj the object whose field should be modified
     * @param d   the new value for the field of <code>obj</code>
     * being modified
     * 
     * @exception IllegalAccessException    if the underlying field
     *              is inaccessible.
     * @exception IllegalArgumentException  if the specified object is not an
     *              instance of the class or interface declaring the underlying
     *              field (or a subclass or implementor thereof), 
     *              or if an unwrapping conversion fails.
     * @exception NullPointerException      if the specified object is null
     *              and the field is an instance field.
     * @exception ExceptionInInitializerError if the initialization provoked
     *              by this method fails.
     * @see       Field#set
     */
    public void setDouble(Object obj, double d)
	throws IllegalArgumentException, IllegalAccessException
    {
        getFieldAccessor(obj).setDouble(obj, d);
    }

    // Convenience routine which performs security checks
    private FieldAccessor getFieldAccessor(Object obj)
        throws IllegalAccessException
    {
        doSecurityCheck(obj);
        if (fieldAccessor == null) {
            acquireFieldAccessor();
        }
        return fieldAccessor;
    }

    // NOTE that there is no synchronization used here. It is correct
    // (though not efficient) to generate more than one FieldAccessor
    // for a given Field. However, avoiding synchronization will
    // probably make the implementation more scalable.
    private void acquireFieldAccessor() {
        // First check to see if one has been created yet, and take it
        // if so
        FieldAccessor tmp = null;
        if (root != null) tmp = root.getFieldAccessor();
        if (tmp != null) {
            fieldAccessor = tmp;
            return;
        }
        // Otherwise fabricate one and propagate it up to the root
        tmp = reflectionFactory.newFieldAccessor(this);
        setFieldAccessor(tmp);
    }

    // Returns FieldAccessor for this Field object, not looking up
    // the chain to the root
    private FieldAccessor getFieldAccessor() {
        return fieldAccessor;
    }

    // Sets the FieldAccessor for this Field object and
    // (recursively) its root
    private void setFieldAccessor(FieldAccessor accessor) {
        fieldAccessor = accessor;
        // Propagate up
        if (root != null) {
            root.setFieldAccessor(accessor);
        }
    }

    // NOTE: be very careful if you change the stack depth of this
    // routine. The depth of the "getCallerClass" call is hardwired so
    // that the compiler can have an easier time if this gets inlined.
    private void doSecurityCheck(Object obj) throws IllegalAccessException {
        if (!override) {
            if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
                Class caller = Reflection.getCallerClass(4);
                Class targetClass = ((obj == null || !Modifier.isProtected(modifiers))
                                     ? clazz
                                     : obj.getClass());
                if (securityCheckCache != caller ||
                    targetClass != securityCheckTargetClassCache) {
                    Reflection.ensureMemberAccess(caller, clazz, obj, modifiers);
                    securityCheckCache = caller;
                    securityCheckTargetClassCache = targetClass;
                }
            }
        }
    }

    /*
     * Utility routine to paper over array type names
     */
    static String getTypeName(Class type) {
	if (type.isArray()) {
	    try {
		Class cl = type;
		int dimensions = 0;
		while (cl.isArray()) {
		    dimensions++;
		    cl = cl.getComponentType();
		}
		StringBuffer sb = new StringBuffer();
		sb.append(cl.getName());
		for (int i = 0; i < dimensions; i++) {
		    sb.append("[]");
		}
		return sb.toString();
	    } catch (Throwable e) { /*FALLTHRU*/ }
	}
	return type.getName();
    }

}