Java Code Examples for sun.reflect.Reflection#getCallerClass()

/**
 * Retrieves an Enumeration with all of the currently loaded JDBC drivers
 * to which the current caller has access.
 *
 * <P><B>Note:</B> The classname of a driver can be found using
 * <CODE>d.getClass().getName()</CODE>
 *
 * @return the list of JDBC Drivers loaded by the caller's class loader
 */
@CallerSensitive
public static java.util.Enumeration<Driver> getDrivers() {
    java.util.Vector<Driver> result = new java.util.Vector<>();

    Class<?> callerClass = Reflection.getCallerClass();

    // Walk through the loaded registeredDrivers.
    for(DriverInfo aDriver : registeredDrivers) {
        // If the caller does not have permission to load the driver then
        // skip it.
        if(isDriverAllowed(aDriver.driver, callerClass)) {
            result.addElement(aDriver.driver);
        } else {
            println("    skipping: " + aDriver.getClass().getName());
        }
    }
    return (result.elements());
}
 

/**
 * Retrieves an Enumeration with all of the currently loaded JDBC drivers
 * to which the current caller has access.
 *
 * <P><B>Note:</B> The classname of a driver can be found using
 * <CODE>d.getClass().getName()</CODE>
 *
 * @return the list of JDBC Drivers loaded by the caller's class loader
 */
@CallerSensitive
public static java.util.Enumeration<Driver> getDrivers() {
    java.util.Vector<Driver> result = new java.util.Vector<>();

    Class<?> callerClass = Reflection.getCallerClass();

    // Walk through the loaded registeredDrivers.
    for(DriverInfo aDriver : registeredDrivers) {
        // If the caller does not have permission to load the driver then
        // skip it.
        if(isDriverAllowed(aDriver.driver, callerClass)) {
            result.addElement(aDriver.driver);
        } else {
            println("    skipping: " + aDriver.getClass().getName());
        }
    }
    return (result.elements());
}
 

/**
 * Returns the invocation handler for the specified proxy instance.
 *
 * @param   proxy the proxy instance to return the invocation handler for
 * @return  the invocation handler for the proxy instance
 * @throws  IllegalArgumentException if the argument is not a
 *          proxy instance
 * @throws  SecurityException if a security manager, <em>s</em>, is present
 *          and the caller's class loader is not the same as or an
 *          ancestor of the class loader for the invocation handler
 *          and invocation of {@link SecurityManager#checkPackageAccess
 *          s.checkPackageAccess()} denies access to the invocation
 *          handler's class.
 */
@CallerSensitive
public static InvocationHandler getInvocationHandler(Object proxy)
    throws IllegalArgumentException
{
    /*
     * Verify that the object is actually a proxy instance.
     */
    if (!isProxyClass(proxy.getClass())) {
        throw new IllegalArgumentException("not a proxy instance");
    }

    final Proxy p = (Proxy) proxy;
    final InvocationHandler ih = p.h;
    if (System.getSecurityManager() != null) {
        Class<?> ihClass = ih.getClass();
        Class<?> caller = Reflection.getCallerClass();
        if (ReflectUtil.needsPackageAccessCheck(caller.getClassLoader(),
                                                ihClass.getClassLoader()))
        {
            ReflectUtil.checkPackageAccess(ihClass);
        }
    }

    return ih;
}
 

/**
 * Get the type of the field.  If the type is non-primitive and this
 * <code>ObjectStreamField</code> was obtained from a deserialized {@link
 * ObjectStreamClass} instance, then <code>Object.class</code> is returned.
 * Otherwise, the <code>Class</code> object for the type of the field is
 * returned.
 *
 * @return  a <code>Class</code> object representing the type of the
 *          serializable field
 */
@CallerSensitive
public Class<?> getType() {
    if (System.getSecurityManager() != null) {
        Class<?> caller = Reflection.getCallerClass();
        if (ReflectUtil.needsPackageAccessCheck(caller.getClassLoader(), type.getClassLoader())) {
            ReflectUtil.checkPackageAccess(type);
        }
    }
    return type;
}
 

/**
 * Performs the specified {@code PrivilegedAction} with privileges
 * enabled and restricted by the specified
 * {@code AccessControlContext} and with a privilege scope limited
 * by specified {@code Permission} arguments.
 *
 * The action is performed with the intersection of the permissions
 * possessed by the caller's protection domain, and those possessed
 * by the domains represented by the specified
 * {@code AccessControlContext}.
 * <p>
 * If the action's {@code run} method throws an (unchecked) exception,
 * it will propagate through this method.
 *
 * <p> This method preserves the current AccessControlContext's
 * DomainCombiner (which may be null) while the action is performed.
 * <p>
 * If a security manager is installed and the specified
 * {@code AccessControlContext} was not created by system code and the
 * caller's {@code ProtectionDomain} has not been granted the
 * {@literal "createAccessControlContext"}
 * {@link java.security.SecurityPermission}, then the action is performed
 * with no permissions.
 *
 * @param <T> the type of the value returned by the PrivilegedAction's
 *                  {@code run} method.
 * @param action the action to be performed.
 * @param context an <i>access control context</i>
 *                representing the restriction to be applied to the
 *                caller's domain's privileges before performing
 *                the specified action.  If the context is
 *                {@code null},
 *                then no additional restriction is applied.
 * @param perms the {@code Permission} arguments which limit the
 *              scope of the caller's privileges. The number of arguments
 *              is variable.
 *
 * @return the value returned by the action's {@code run} method.
 *
 * @throws NullPointerException if action or perms or any element of
 *         perms is {@code null}
 *
 * @see #doPrivileged(PrivilegedAction)
 * @see #doPrivileged(PrivilegedExceptionAction,AccessControlContext)
 * @see java.security.DomainCombiner
 *
 * @since 1.8
 */
@CallerSensitive
public static <T> T doPrivilegedWithCombiner(PrivilegedAction<T> action,
    AccessControlContext context, Permission... perms) {

    AccessControlContext parent = getContext();
    DomainCombiner dc = parent.getCombiner();
    if (dc == null && context != null) {
        dc = context.getCombiner();
    }
    if (perms == null) {
        throw new NullPointerException("null permissions parameter");
    }
    Class <?> caller = Reflection.getCallerClass();
    return AccessController.doPrivileged(action, createWrapper(dc, caller,
        parent, context, perms));
}
 

/**
 * Performs the specified {@code PrivilegedExceptionAction} with
 * privileges enabled and restricted by the specified
 * {@code AccessControlContext} and with a privilege scope limited by
 * specified {@code Permission} arguments.
 *
 * The action is performed with the intersection of the permissions
 * possessed by the caller's protection domain, and those possessed
 * by the domains represented by the specified
 * {@code AccessControlContext}.
 * <p>
 * If the action's {@code run} method throws an (unchecked) exception,
 * it will propagate through this method.
 *
 * <p> This method preserves the current AccessControlContext's
 * DomainCombiner (which may be null) while the action is performed.
 * <p>
 * If a security manager is installed and the specified
 * {@code AccessControlContext} was not created by system code and the
 * caller's {@code ProtectionDomain} has not been granted the
 * {@literal "createAccessControlContext"}
 * {@link java.security.SecurityPermission}, then the action is performed
 * with no permissions.
 *
 * @param <T> the type of the value returned by the
 *                  PrivilegedExceptionAction's {@code run} method.
 * @param action the action to be performed.
 * @param context an <i>access control context</i>
 *                representing the restriction to be applied to the
 *                caller's domain's privileges before performing
 *                the specified action.  If the context is
 *                {@code null},
 *                then no additional restriction is applied.
 * @param perms the {@code Permission} arguments which limit the
 *              scope of the caller's privileges. The number of arguments
 *              is variable.
 *
 * @return the value returned by the action's {@code run} method.
 *
 * @throws PrivilegedActionException if the specified action's
 *         {@code run} method threw a <i>checked</i> exception
 * @throws NullPointerException if action or perms or any element of
 *         perms is {@code null}
 *
 * @see #doPrivileged(PrivilegedAction)
 * @see #doPrivileged(PrivilegedAction,AccessControlContext)
 * @see java.security.DomainCombiner
 *
 * @since 1.8
 */
@CallerSensitive
public static <T> T doPrivilegedWithCombiner(PrivilegedExceptionAction<T> action,
                                             AccessControlContext context,
                                             Permission... perms)
    throws PrivilegedActionException
{
    AccessControlContext parent = getContext();
    DomainCombiner dc = parent.getCombiner();
    if (dc == null && context != null) {
        dc = context.getCombiner();
    }
    if (perms == null) {
        throw new NullPointerException("null permissions parameter");
    }
    Class <?> caller = Reflection.getCallerClass();
    return AccessController.doPrivileged(action, createWrapper(dc, caller,
        parent, context, perms));
}
 

static void deepest() {
    // 0: Reflection 1: deepest 2: deeper 3: deep 4: Test.selfTest
    Class<?> c = Reflection.getCallerClass(4);
    assertEquals(c, Test.class);
}
 

/**
 * Invokes the underlying method represented by this {@code Method}
 * object, on the specified object with the specified parameters.
 * Individual parameters are automatically unwrapped to match
 * primitive formal parameters, and both primitive and reference
 * parameters are subject to method invocation conversions as
 * necessary.
 *
 * <p>If the underlying method is static, then the specified {@code obj}
 * argument is ignored. It may be null.
 *
 * <p>If the number of formal parameters required by the underlying method is
 * 0, the supplied {@code args} array may be of length 0 or null.
 *
 * <p>If the underlying method is an instance method, it is invoked
 * using dynamic method lookup as documented in The Java Language
 * Specification, Second Edition, section 15.12.4.4; in particular,
 * overriding based on the runtime type of the target object will occur.
 *
 * <p>If the underlying method is static, the class that declared
 * the method is initialized if it has not already been initialized.
 *
 * <p>If the method completes normally, the value it returns is
 * returned to the caller of invoke; if the value has a primitive
 * type, it is first appropriately wrapped in an object. However,
 * if the value has the type of an array of a primitive type, the
 * elements of the array are <i>not</i> wrapped in objects; in
 * other words, an array of primitive type is returned.  If the
 * underlying method return type is void, the invocation returns
 * null.
 *
 * @param obj  the object the underlying method is invoked from
 * @param args the arguments used for the method call
 * @return the result of dispatching the method represented by
 * this object on {@code obj} with parameters
 * {@code args}
 *
 * @exception IllegalAccessException    if this {@code Method} object
 *              is enforcing Java language access control and the underlying
 *              method is inaccessible.
 * @exception IllegalArgumentException  if the method is an
 *              instance method and the specified object argument
 *              is not an instance of the class or interface
 *              declaring the underlying method (or of a subclass
 *              or implementor thereof); if the number of actual
 *              and formal parameters differ; if an unwrapping
 *              conversion for primitive arguments fails; or if,
 *              after possible unwrapping, a parameter value
 *              cannot be converted to the corresponding formal
 *              parameter type by a method invocation conversion.
 * @exception InvocationTargetException if the underlying method
 *              throws an exception.
 * @exception NullPointerException      if the specified object is null
 *              and the method is an instance method.
 * @exception ExceptionInInitializerError if the initialization
 * provoked by this method fails.
 */
@CallerSensitive
public Object invoke(Object obj, Object... args)
    throws IllegalAccessException, IllegalArgumentException,
       InvocationTargetException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    MethodAccessor ma = methodAccessor;             // read volatile
    if (ma == null) {
        ma = acquireMethodAccessor();
    }
    return ma.invoke(obj, args);
}
 

/**
 * Uses the constructor represented by this {@code Constructor} object to
 * create and initialize a new instance of the constructor's
 * declaring class, with the specified initialization parameters.
 * Individual parameters are automatically unwrapped to match
 * primitive formal parameters, and both primitive and reference
 * parameters are subject to method invocation conversions as necessary.
 *
 * <p>If the number of formal parameters required by the underlying constructor
 * is 0, the supplied {@code initargs} array may be of length 0 or null.
 *
 * <p>If the constructor's declaring class is an inner class in a
 * non-static context, the first argument to the constructor needs
 * to be the enclosing instance; see section 15.9.3 of
 * <cite>The Java&trade; Language Specification</cite>.
 *
 * <p>If the required access and argument checks succeed and the
 * instantiation will proceed, the constructor's declaring class
 * is initialized if it has not already been initialized.
 *
 * <p>If the constructor completes normally, returns the newly
 * created and initialized instance.
 *
 * @param initargs array of objects to be passed as arguments to
 * the constructor call; values of primitive types are wrapped in
 * a wrapper object of the appropriate type (e.g. a {@code float}
 * in a {@link java.lang.Float Float})
 *
 * @return a new object created by calling the constructor
 * this object represents
 *
 * @exception IllegalAccessException    if this {@code Constructor} object
 *              is enforcing Java language access control and the underlying
 *              constructor is inaccessible.
 * @exception IllegalArgumentException  if the number of actual
 *              and formal parameters differ; if an unwrapping
 *              conversion for primitive arguments fails; or if,
 *              after possible unwrapping, a parameter value
 *              cannot be converted to the corresponding formal
 *              parameter type by a method invocation conversion; if
 *              this constructor pertains to an enum type.
 * @exception InstantiationException    if the class that declares the
 *              underlying constructor represents an abstract class.
 * @exception InvocationTargetException if the underlying constructor
 *              throws an exception.
 * @exception ExceptionInInitializerError if the initialization provoked
 *              by this method fails.
 */
@CallerSensitive
public T newInstance(Object ... initargs)
    throws InstantiationException, IllegalAccessException,
           IllegalArgumentException, InvocationTargetException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, null, modifiers);
        }
    }
    if ((clazz.getModifiers() & Modifier.ENUM) != 0)
        throw new IllegalArgumentException("Cannot reflectively create enum objects");
    ConstructorAccessor ca = constructorAccessor;   // read volatile
    if (ca == null) {
        ca = acquireConstructorAccessor();
    }
    @SuppressWarnings("unchecked")
    T inst = (T) ca.newInstance(initargs);
    return inst;
}
 

/**
 * Sets the value of a field as a {@code short} on the specified object.
 * This method is equivalent to
 * {@code set(obj, sObj)},
 * where {@code sObj} is a {@code Short} object and
 * {@code sObj.shortValue() == s}.
 *
 * @param obj the object whose field should be modified
 * @param s   the new value for the field of {@code obj}
 * being modified
 *
 * @exception IllegalAccessException    if this {@code Field} object
 *              is enforcing Java language access control and the underlying
 *              field is either inaccessible or final.
 * @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
 */
@CallerSensitive
public void setShort(Object obj, short s)
    throws IllegalArgumentException, IllegalAccessException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    getFieldAccessor(obj).setShort(obj, s);
}
 

/**
 * Gets the value of a static or instance field of type
 * {@code char} or of another primitive type convertible to
 * type {@code char} via a widening conversion.
 *
 * @param obj the object to extract the {@code char} value
 * from
 * @return the value of the field converted to type {@code char}
 *
 * @exception IllegalAccessException    if this {@code Field} object
 *              is enforcing Java language access control and 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 the field value cannot be
 *              converted to the type {@code char} by a
 *              widening conversion.
 * @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#get
 */
@CallerSensitive
public char getChar(Object obj)
    throws IllegalArgumentException, IllegalAccessException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    return getFieldAccessor(obj).getChar(obj);
}
 

/**
 * Gets the value of a static or instance {@code boolean} field.
 *
 * @param obj the object to extract the {@code boolean} value
 * from
 * @return the value of the {@code boolean} field
 *
 * @exception IllegalAccessException    if this {@code Field} object
 *              is enforcing Java language access control and 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 the field value cannot be
 *              converted to the type {@code boolean} by a
 *              widening conversion.
 * @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#get
 */
@CallerSensitive
public boolean getBoolean(Object obj)
    throws IllegalArgumentException, IllegalAccessException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    return getFieldAccessor(obj).getBoolean(obj);
}
 

/**
 * Sets the value of a field as a {@code char} on the specified object.
 * This method is equivalent to
 * {@code set(obj, cObj)},
 * where {@code cObj} is a {@code Character} object and
 * {@code cObj.charValue() == c}.
 *
 * @param obj the object whose field should be modified
 * @param c   the new value for the field of {@code obj}
 * being modified
 *
 * @exception IllegalAccessException    if this {@code Field} object
 *              is enforcing Java language access control and the underlying
 *              field is either inaccessible or final.
 * @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
 */
@CallerSensitive
public void setChar(Object obj, char c)
    throws IllegalArgumentException, IllegalAccessException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    getFieldAccessor(obj).setChar(obj, c);
}
 

/**
 * Gets the value of a static or instance field of type
 * {@code long} or of another primitive type convertible to
 * type {@code long} via a widening conversion.
 *
 * @param obj the object to extract the {@code long} value
 * from
 * @return the value of the field converted to type {@code long}
 *
 * @exception IllegalAccessException    if this {@code Field} object
 *              is enforcing Java language access control and 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 the field value cannot be
 *              converted to the type {@code long} by a
 *              widening conversion.
 * @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#get
 */
@CallerSensitive
public long getLong(Object obj)
    throws IllegalArgumentException, IllegalAccessException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    return getFieldAccessor(obj).getLong(obj);
}
 

/**
 * Gets the value of a static or instance field of type
 * {@code long} or of another primitive type convertible to
 * type {@code long} via a widening conversion.
 *
 * @param obj the object to extract the {@code long} value
 * from
 * @return the value of the field converted to type {@code long}
 *
 * @exception IllegalAccessException    if this {@code Field} object
 *              is enforcing Java language access control and 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 the field value cannot be
 *              converted to the type {@code long} by a
 *              widening conversion.
 * @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#get
 */
@CallerSensitive
public long getLong(Object obj)
    throws IllegalArgumentException, IllegalAccessException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    return getFieldAccessor(obj).getLong(obj);
}
 

/**
 * Performs the specified {@code PrivilegedAction} with privileges
 * enabled and restricted by the specified
 * {@code AccessControlContext} and with a privilege scope limited
 * by specified {@code Permission} arguments.
 *
 * The action is performed with the intersection of the permissions
 * possessed by the caller's protection domain, and those possessed
 * by the domains represented by the specified
 * {@code AccessControlContext}.
 * <p>
 * If the action's {@code run} method throws an (unchecked) exception,
 * it will propagate through this method.
 * <p>
 * If a security manager is installed and the specified
 * {@code AccessControlContext} was not created by system code and the
 * caller's {@code ProtectionDomain} has not been granted the
 * {@literal "createAccessControlContext"}
 * {@link java.security.SecurityPermission}, then the action is performed
 * with no permissions.
 *
 * @param <T> the type of the value returned by the PrivilegedAction's
 *                  {@code run} method.
 * @param action the action to be performed.
 * @param context an <i>access control context</i>
 *                representing the restriction to be applied to the
 *                caller's domain's privileges before performing
 *                the specified action.  If the context is
 *                {@code null},
 *                then no additional restriction is applied.
 * @param perms the {@code Permission} arguments which limit the
 *              scope of the caller's privileges. The number of arguments
 *              is variable.
 *
 * @return the value returned by the action's {@code run} method.
 *
 * @throws NullPointerException if action or perms or any element of
 *         perms is {@code null}
 *
 * @see #doPrivileged(PrivilegedAction)
 * @see #doPrivileged(PrivilegedExceptionAction,AccessControlContext)
 *
 * @since 1.8
 */
@CallerSensitive
public static <T> T doPrivileged(PrivilegedAction<T> action,
    AccessControlContext context, Permission... perms) {

    AccessControlContext parent = getContext();
    if (perms == null) {
        throw new NullPointerException("null permissions parameter");
    }
    Class <?> caller = Reflection.getCallerClass();
    return AccessController.doPrivileged(action, createWrapper(null,
        caller, parent, context, perms));
}
 

/**
 * Creates and returns an updater for objects with the given field.
 * The Class argument is needed to check that reflective types and
 * generic types match.
 *
 * @param tclass the class of the objects holding the field
 * @param fieldName the name of the field to be updated
 * @param <U> the type of instances of tclass
 * @return the updater
 * @throws IllegalArgumentException if the field is not a
 * volatile long type
 * @throws RuntimeException with a nested reflection-based
 * exception if the class does not hold field or is the wrong type,
 * or the field is inaccessible to the caller according to Java language
 * access control
 */
@CallerSensitive
public static <U> AtomicLongFieldUpdater<U> newUpdater(Class<U> tclass,
                                                       String fieldName) {
    Class<?> caller = Reflection.getCallerClass();
    if (AtomicLong.VM_SUPPORTS_LONG_CAS)
        return new CASUpdater<U>(tclass, fieldName, caller);
    else
        return new LockedUpdater<U>(tclass, fieldName, caller);
}
 

/**
 * Sets the value of a field as an {@code int} on the specified object.
 * This method is equivalent to
 * {@code set(obj, iObj)},
 * where {@code iObj} is a {@code Integer} object and
 * {@code iObj.intValue() == i}.
 *
 * @param obj the object whose field should be modified
 * @param i   the new value for the field of {@code obj}
 * being modified
 *
 * @exception IllegalAccessException    if this {@code Field} object
 *              is enforcing Java language access control and the underlying
 *              field is either inaccessible or final.
 * @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
 */
@CallerSensitive
public void setInt(Object obj, int i)
    throws IllegalArgumentException, IllegalAccessException
{
    if (!override) {
        if (!Reflection.quickCheckMemberAccess(clazz, modifiers)) {
            Class<?> caller = Reflection.getCallerClass();
            checkAccess(caller, clazz, obj, modifiers);
        }
    }
    getFieldAccessor(obj).setInt(obj, i);
}
 

/**
 * Creates and returns an updater for objects with the given field.
 * The Class arguments are needed to check that reflective types and
 * generic types match.
 *
 * @param tclass the class of the objects holding the field
 * @param vclass the class of the field
 * @param fieldName the name of the field to be updated
 * @param <U> the type of instances of tclass
 * @param <W> the type of instances of vclass
 * @return the updater
 * @throws ClassCastException if the field is of the wrong type
 * @throws IllegalArgumentException if the field is not volatile
 * @throws RuntimeException with a nested reflection-based
 * exception if the class does not hold field or is the wrong type,
 * or the field is inaccessible to the caller according to Java language
 * access control
 */
@CallerSensitive
public static <U,W> AtomicReferenceFieldUpdater<U,W> newUpdater(Class<U> tclass,
                                                                Class<W> vclass,
                                                                String fieldName) {
    return new AtomicReferenceFieldUpdaterImpl<U,W>
        (tclass, vclass, fieldName, Reflection.getCallerClass());
}
 

/**
 * Returns a {@link Lookup lookup object} with
 * full capabilities to emulate all supported bytecode behaviors of the caller.
 * These capabilities include <a href="MethodHandles.Lookup.html#privacc">private access</a> to the caller.
 * Factory methods on the lookup object can create
 * <a href="MethodHandleInfo.html#directmh">direct method handles</a>
 * for any member that the caller has access to via bytecodes,
 * including protected and private fields and methods.
 * This lookup object is a <em>capability</em> which may be delegated to trusted agents.
 * Do not store it in place where untrusted code can access it.
 * <p>
 * This method is caller sensitive, which means that it may return different
 * values to different callers.
 * <p>
 * For any given caller class {@code C}, the lookup object returned by this call
 * has equivalent capabilities to any lookup object
 * supplied by the JVM to the bootstrap method of an
 * <a href="package-summary.html#indyinsn">invokedynamic instruction</a>
 * executing in the same caller class {@code C}.
 * @return a lookup object for the caller of this method, with private access
 */
@CallerSensitive
public static Lookup lookup() {
    return new Lookup(Reflection.getCallerClass());
}