| /* |
| * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.lang.reflect; |
| |
| import java.lang.module.ModuleDescriptor; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.util.Arrays; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.IdentityHashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.Set; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import java.util.concurrent.atomic.AtomicLong; |
| import java.util.stream.Collectors; |
| import java.util.stream.Stream; |
| |
| import jdk.internal.loader.BootLoader; |
| import jdk.internal.module.Modules; |
| import jdk.internal.misc.Unsafe; |
| import jdk.internal.misc.VM; |
| import jdk.internal.reflect.CallerSensitive; |
| import jdk.internal.reflect.Reflection; |
| import jdk.internal.loader.ClassLoaderValue; |
| import sun.reflect.misc.ReflectUtil; |
| import sun.security.action.GetPropertyAction; |
| import sun.security.util.SecurityConstants; |
| |
| import static java.lang.module.ModuleDescriptor.Modifier.SYNTHETIC; |
| |
| |
| /** |
| * |
| * {@code Proxy} provides static methods for creating objects that act like instances |
| * of interfaces but allow for customized method invocation. |
| * To create a proxy instance for some interface {@code Foo}: |
| * <pre>{@code |
| * InvocationHandler handler = new MyInvocationHandler(...); |
| * Foo f = (Foo) Proxy.newProxyInstance(Foo.class.getClassLoader(), |
| * new Class<?>[] { Foo.class }, |
| * handler); |
| * }</pre> |
| * |
| * <p> |
| * A <em>proxy class</em> is a class created at runtime that implements a specified |
| * list of interfaces, known as <em>proxy interfaces</em>. A <em>proxy instance</em> |
| * is an instance of a proxy class. |
| * |
| * Each proxy instance has an associated <i>invocation handler</i> |
| * object, which implements the interface {@link InvocationHandler}. |
| * A method invocation on a proxy instance through one of its proxy |
| * interfaces will be dispatched to the {@link InvocationHandler#invoke |
| * invoke} method of the instance's invocation handler, passing the proxy |
| * instance, a {@code java.lang.reflect.Method} object identifying |
| * the method that was invoked, and an array of type {@code Object} |
| * containing the arguments. The invocation handler processes the |
| * encoded method invocation as appropriate and the result that it |
| * returns will be returned as the result of the method invocation on |
| * the proxy instance. |
| * |
| * <p>A proxy class has the following properties: |
| * |
| * <ul> |
| * <li>The unqualified name of a proxy class is unspecified. The space |
| * of class names that begin with the string {@code "$Proxy"} |
| * should be, however, reserved for proxy classes. |
| * |
| * <li>The package and module in which a proxy class is defined is specified |
| * <a href="#membership">below</a>. |
| * |
| * <li>A proxy class is <em>final and non-abstract</em>. |
| * |
| * <li>A proxy class extends {@code java.lang.reflect.Proxy}. |
| * |
| * <li>A proxy class implements exactly the interfaces specified at its |
| * creation, in the same order. Invoking {@link Class#getInterfaces getInterfaces} |
| * on its {@code Class} object will return an array containing the same |
| * list of interfaces (in the order specified at its creation), invoking |
| * {@link Class#getMethods getMethods} on its {@code Class} object will return |
| * an array of {@code Method} objects that include all of the |
| * methods in those interfaces, and invoking {@code getMethod} will |
| * find methods in the proxy interfaces as would be expected. |
| * |
| * <li>The {@link java.security.ProtectionDomain} of a proxy class |
| * is the same as that of system classes loaded by the bootstrap class |
| * loader, such as {@code java.lang.Object}, because the code for a |
| * proxy class is generated by trusted system code. This protection |
| * domain will typically be granted {@code java.security.AllPermission}. |
| * |
| * <li>The {@link Proxy#isProxyClass Proxy.isProxyClass} method can be used |
| * to determine if a given class is a proxy class. |
| * </ul> |
| * |
| * <p>A proxy instance has the following properties: |
| * |
| * <ul> |
| * <li>Given a proxy instance {@code proxy} and one of the |
| * interfaces, {@code Foo}, implemented by its proxy class, the |
| * following expression will return true: |
| * <pre> |
| * {@code proxy instanceof Foo} |
| * </pre> |
| * and the following cast operation will succeed (rather than throwing |
| * a {@code ClassCastException}): |
| * <pre> |
| * {@code (Foo) proxy} |
| * </pre> |
| * |
| * <li>Each proxy instance has an associated invocation handler, the one |
| * that was passed to its constructor. The static |
| * {@link Proxy#getInvocationHandler Proxy.getInvocationHandler} method |
| * will return the invocation handler associated with the proxy instance |
| * passed as its argument. |
| * |
| * <li>An interface method invocation on a proxy instance will be |
| * encoded and dispatched to the invocation handler's {@link |
| * InvocationHandler#invoke invoke} method as described in the |
| * documentation for that method. |
| * |
| * <li>An invocation of the {@code hashCode}, |
| * {@code equals}, or {@code toString} methods declared in |
| * {@code java.lang.Object} on a proxy instance will be encoded and |
| * dispatched to the invocation handler's {@code invoke} method in |
| * the same manner as interface method invocations are encoded and |
| * dispatched, as described above. The declaring class of the |
| * {@code Method} object passed to {@code invoke} will be |
| * {@code java.lang.Object}. Other public methods of a proxy |
| * instance inherited from {@code java.lang.Object} are not |
| * overridden by a proxy class, so invocations of those methods behave |
| * like they do for instances of {@code java.lang.Object}. |
| * </ul> |
| * |
| * <h3><a id="membership">Package and Module Membership of Proxy Class</a></h3> |
| * |
| * The package and module to which a proxy class belongs are chosen such that |
| * the accessibility of the proxy class is in line with the accessibility of |
| * the proxy interfaces. Specifically, the package and the module membership |
| * of a proxy class defined via the |
| * {@link Proxy#getProxyClass(ClassLoader, Class[])} or |
| * {@link Proxy#newProxyInstance(ClassLoader, Class[], InvocationHandler)} |
| * methods is specified as follows: |
| * |
| * <ol> |
| * <li>If all the proxy interfaces are in <em>exported</em> or <em>open</em> |
| * packages: |
| * <ol type="a"> |
| * <li>if all the proxy interfaces are <em>public</em>, then the proxy class is |
| * <em>public</em> in a package exported by the |
| * {@linkplain ClassLoader#getUnnamedModule() unnamed module} of the specified |
| * loader. The name of the package is unspecified.</li> |
| * |
| * <li>if at least one of all the proxy interfaces is <em>non-public</em>, then |
| * the proxy class is <em>non-public</em> in the package and module of the |
| * non-public interfaces. All the non-public interfaces must be in the same |
| * package and module; otherwise, proxying them is |
| * <a href="#restrictions">not possible</a>.</li> |
| * </ol> |
| * </li> |
| * <li>If at least one proxy interface is in a package that is |
| * <em>non-exported</em> and <em>non-open</em>: |
| * <ol type="a"> |
| * <li>if all the proxy interfaces are <em>public</em>, then the proxy class is |
| * <em>public</em> in a <em>non-exported</em>, <em>non-open</em> package of |
| * <a href="#dynamicmodule"><em>dynamic module</em>.</a> |
| * The names of the package and the module are unspecified.</li> |
| * |
| * <li>if at least one of all the proxy interfaces is <em>non-public</em>, then |
| * the proxy class is <em>non-public</em> in the package and module of the |
| * non-public interfaces. All the non-public interfaces must be in the same |
| * package and module; otherwise, proxying them is |
| * <a href="#restrictions">not possible</a>.</li> |
| * </ol> |
| * </li> |
| * </ol> |
| * |
| * <p> |
| * Note that if proxy interfaces with a mix of accessibilities -- for example, |
| * an exported public interface and a non-exported non-public interface -- are |
| * proxied by the same instance, then the proxy class's accessibility is |
| * governed by the least accessible proxy interface. |
| * <p> |
| * Note that it is possible for arbitrary code to obtain access to a proxy class |
| * in an open package with {@link AccessibleObject#setAccessible setAccessible}, |
| * whereas a proxy class in a non-open package is never accessible to |
| * code outside the module of the proxy class. |
| * |
| * <p> |
| * Throughout this specification, a "non-exported package" refers to a package |
| * that is not exported to all modules, and a "non-open package" refers to |
| * a package that is not open to all modules. Specifically, these terms refer to |
| * a package that either is not exported/open by its containing module or is |
| * exported/open in a qualified fashion by its containing module. |
| * |
| * <h3><a id="dynamicmodule">Dynamic Modules</a></h3> |
| * <p> |
| * A dynamic module is a named module generated at runtime. A proxy class |
| * defined in a dynamic module is encapsulated and not accessible to any module. |
| * Calling {@link Constructor#newInstance(Object...)} on a proxy class in |
| * a dynamic module will throw {@code IllegalAccessException}; |
| * {@code Proxy.newProxyInstance} method should be used instead. |
| * |
| * <p> |
| * A dynamic module can read the modules of all of the superinterfaces of a proxy |
| * class and the modules of the types referenced by all public method signatures |
| * of a proxy class. If a superinterface or a referenced type, say {@code T}, |
| * is in a non-exported package, the {@linkplain Module module} of {@code T} is |
| * updated to export the package of {@code T} to the dynamic module. |
| * |
| * <h3>Methods Duplicated in Multiple Proxy Interfaces</h3> |
| * |
| * <p>When two or more proxy interfaces contain a method with |
| * the same name and parameter signature, the order of the proxy class's |
| * interfaces becomes significant. When such a <i>duplicate method</i> |
| * is invoked on a proxy instance, the {@code Method} object passed |
| * to the invocation handler will not necessarily be the one whose |
| * declaring class is assignable from the reference type of the interface |
| * that the proxy's method was invoked through. This limitation exists |
| * because the corresponding method implementation in the generated proxy |
| * class cannot determine which interface it was invoked through. |
| * Therefore, when a duplicate method is invoked on a proxy instance, |
| * the {@code Method} object for the method in the foremost interface |
| * that contains the method (either directly or inherited through a |
| * superinterface) in the proxy class's list of interfaces is passed to |
| * the invocation handler's {@code invoke} method, regardless of the |
| * reference type through which the method invocation occurred. |
| * |
| * <p>If a proxy interface contains a method with the same name and |
| * parameter signature as the {@code hashCode}, {@code equals}, |
| * or {@code toString} methods of {@code java.lang.Object}, |
| * when such a method is invoked on a proxy instance, the |
| * {@code Method} object passed to the invocation handler will have |
| * {@code java.lang.Object} as its declaring class. In other words, |
| * the public, non-final methods of {@code java.lang.Object} |
| * logically precede all of the proxy interfaces for the determination of |
| * which {@code Method} object to pass to the invocation handler. |
| * |
| * <p>Note also that when a duplicate method is dispatched to an |
| * invocation handler, the {@code invoke} method may only throw |
| * checked exception types that are assignable to one of the exception |
| * types in the {@code throws} clause of the method in <i>all</i> of |
| * the proxy interfaces that it can be invoked through. If the |
| * {@code invoke} method throws a checked exception that is not |
| * assignable to any of the exception types declared by the method in one |
| * of the proxy interfaces that it can be invoked through, then an |
| * unchecked {@code UndeclaredThrowableException} will be thrown by |
| * the invocation on the proxy instance. This restriction means that not |
| * all of the exception types returned by invoking |
| * {@code getExceptionTypes} on the {@code Method} object |
| * passed to the {@code invoke} method can necessarily be thrown |
| * successfully by the {@code invoke} method. |
| * |
| * @author Peter Jones |
| * @see InvocationHandler |
| * @since 1.3 |
| * @revised 9 |
| * @spec JPMS |
| */ |
| public class Proxy implements java.io.Serializable { |
| private static final long serialVersionUID = -2222568056686623797L; |
| |
| /** parameter types of a proxy class constructor */ |
| private static final Class<?>[] constructorParams = |
| { InvocationHandler.class }; |
| |
| /** |
| * a cache of proxy constructors with |
| * {@link Constructor#setAccessible(boolean) accessible} flag already set |
| */ |
| private static final ClassLoaderValue<Constructor<?>> proxyCache = |
| new ClassLoaderValue<>(); |
| |
| /** |
| * the invocation handler for this proxy instance. |
| * @serial |
| */ |
| protected InvocationHandler h; |
| |
| /** |
| * Prohibits instantiation. |
| */ |
| private Proxy() { |
| } |
| |
| /** |
| * Constructs a new {@code Proxy} instance from a subclass |
| * (typically, a dynamic proxy class) with the specified value |
| * for its invocation handler. |
| * |
| * @param h the invocation handler for this proxy instance |
| * |
| * @throws NullPointerException if the given invocation handler, {@code h}, |
| * is {@code null}. |
| */ |
| protected Proxy(InvocationHandler h) { |
| Objects.requireNonNull(h); |
| this.h = h; |
| } |
| |
| /** |
| * Returns the {@code java.lang.Class} object for a proxy class |
| * given a class loader and an array of interfaces. The proxy class |
| * will be defined by the specified class loader and will implement |
| * all of the supplied interfaces. If any of the given interfaces |
| * is non-public, the proxy class will be non-public. If a proxy class |
| * for the same permutation of interfaces has already been defined by the |
| * class loader, then the existing proxy class will be returned; otherwise, |
| * a proxy class for those interfaces will be generated dynamically |
| * and defined by the class loader. |
| * |
| * @param loader the class loader to define the proxy class |
| * @param interfaces the list of interfaces for the proxy class |
| * to implement |
| * @return a proxy class that is defined in the specified class loader |
| * and that implements the specified interfaces |
| * @throws IllegalArgumentException if any of the <a href="#restrictions"> |
| * restrictions</a> on the parameters are violated |
| * @throws SecurityException if a security manager, <em>s</em>, is present |
| * and any of the following conditions is met: |
| * <ul> |
| * <li> the given {@code loader} is {@code null} and |
| * the caller's class loader is not {@code null} and the |
| * invocation of {@link SecurityManager#checkPermission |
| * s.checkPermission} with |
| * {@code RuntimePermission("getClassLoader")} permission |
| * denies access.</li> |
| * <li> for each proxy interface, {@code intf}, |
| * the caller's class loader is not the same as or an |
| * ancestor of the class loader for {@code intf} and |
| * invocation of {@link SecurityManager#checkPackageAccess |
| * s.checkPackageAccess()} denies access to {@code intf}.</li> |
| * </ul> |
| * @throws NullPointerException if the {@code interfaces} array |
| * argument or any of its elements are {@code null} |
| * |
| * @deprecated Proxy classes generated in a named module are encapsulated |
| * and not accessible to code outside its module. |
| * {@link Constructor#newInstance(Object...) Constructor.newInstance} |
| * will throw {@code IllegalAccessException} when it is called on |
| * an inaccessible proxy class. |
| * Use {@link #newProxyInstance(ClassLoader, Class[], InvocationHandler)} |
| * to create a proxy instance instead. |
| * |
| * @see <a href="#membership">Package and Module Membership of Proxy Class</a> |
| * @revised 9 |
| * @spec JPMS |
| */ |
| @Deprecated |
| @CallerSensitive |
| public static Class<?> getProxyClass(ClassLoader loader, |
| Class<?>... interfaces) |
| throws IllegalArgumentException |
| { |
| Class<?> caller = System.getSecurityManager() == null |
| ? null |
| : Reflection.getCallerClass(); |
| |
| return getProxyConstructor(caller, loader, interfaces) |
| .getDeclaringClass(); |
| } |
| |
| /** |
| * Returns the {@code Constructor} object of a proxy class that takes a |
| * single argument of type {@link InvocationHandler}, given a class loader |
| * and an array of interfaces. The returned constructor will have the |
| * {@link Constructor#setAccessible(boolean) accessible} flag already set. |
| * |
| * @param caller passed from a public-facing @CallerSensitive method if |
| * SecurityManager is set or {@code null} if there's no |
| * SecurityManager |
| * @param loader the class loader to define the proxy class |
| * @param interfaces the list of interfaces for the proxy class |
| * to implement |
| * @return a Constructor of the proxy class taking single |
| * {@code InvocationHandler} parameter |
| */ |
| private static Constructor<?> getProxyConstructor(Class<?> caller, |
| ClassLoader loader, |
| Class<?>... interfaces) |
| { |
| // optimization for single interface |
| if (interfaces.length == 1) { |
| Class<?> intf = interfaces[0]; |
| if (caller != null) { |
| checkProxyAccess(caller, loader, intf); |
| } |
| return proxyCache.sub(intf).computeIfAbsent( |
| loader, |
| (ld, clv) -> new ProxyBuilder(ld, clv.key()).build() |
| ); |
| } else { |
| // interfaces cloned |
| final Class<?>[] intfsArray = interfaces.clone(); |
| if (caller != null) { |
| checkProxyAccess(caller, loader, intfsArray); |
| } |
| final List<Class<?>> intfs = Arrays.asList(intfsArray); |
| return proxyCache.sub(intfs).computeIfAbsent( |
| loader, |
| (ld, clv) -> new ProxyBuilder(ld, clv.key()).build() |
| ); |
| } |
| } |
| |
| /* |
| * Check permissions required to create a Proxy class. |
| * |
| * To define a proxy class, it performs the access checks as in |
| * Class.forName (VM will invoke ClassLoader.checkPackageAccess): |
| * 1. "getClassLoader" permission check if loader == null |
| * 2. checkPackageAccess on the interfaces it implements |
| * |
| * To get a constructor and new instance of a proxy class, it performs |
| * the package access check on the interfaces it implements |
| * as in Class.getConstructor. |
| * |
| * If an interface is non-public, the proxy class must be defined by |
| * the defining loader of the interface. If the caller's class loader |
| * is not the same as the defining loader of the interface, the VM |
| * will throw IllegalAccessError when the generated proxy class is |
| * being defined. |
| */ |
| private static void checkProxyAccess(Class<?> caller, |
| ClassLoader loader, |
| Class<?> ... interfaces) |
| { |
| SecurityManager sm = System.getSecurityManager(); |
| if (sm != null) { |
| ClassLoader ccl = caller.getClassLoader(); |
| if (VM.isSystemDomainLoader(loader) && !VM.isSystemDomainLoader(ccl)) { |
| sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION); |
| } |
| ReflectUtil.checkProxyPackageAccess(ccl, interfaces); |
| } |
| } |
| |
| /** |
| * Builder for a proxy class. |
| * |
| * If the module is not specified in this ProxyBuilder constructor, |
| * it will map from the given loader and interfaces to the module |
| * in which the proxy class will be defined. |
| */ |
| private static final class ProxyBuilder { |
| private static final Unsafe UNSAFE = Unsafe.getUnsafe(); |
| |
| // prefix for all proxy class names |
| private static final String proxyClassNamePrefix = "$Proxy"; |
| |
| // next number to use for generation of unique proxy class names |
| private static final AtomicLong nextUniqueNumber = new AtomicLong(); |
| |
| // a reverse cache of defined proxy classes |
| private static final ClassLoaderValue<Boolean> reverseProxyCache = |
| new ClassLoaderValue<>(); |
| |
| private static Class<?> defineProxyClass(Module m, List<Class<?>> interfaces) { |
| String proxyPkg = null; // package to define proxy class in |
| int accessFlags = Modifier.PUBLIC | Modifier.FINAL; |
| |
| /* |
| * Record the package of a non-public proxy interface so that the |
| * proxy class will be defined in the same package. Verify that |
| * all non-public proxy interfaces are in the same package. |
| */ |
| for (Class<?> intf : interfaces) { |
| int flags = intf.getModifiers(); |
| if (!Modifier.isPublic(flags)) { |
| accessFlags = Modifier.FINAL; // non-public, final |
| String pkg = intf.getPackageName(); |
| if (proxyPkg == null) { |
| proxyPkg = pkg; |
| } else if (!pkg.equals(proxyPkg)) { |
| throw new IllegalArgumentException( |
| "non-public interfaces from different packages"); |
| } |
| } |
| } |
| |
| if (proxyPkg == null) { |
| // all proxy interfaces are public |
| proxyPkg = m.isNamed() ? PROXY_PACKAGE_PREFIX + "." + m.getName() |
| : PROXY_PACKAGE_PREFIX; |
| } else if (proxyPkg.isEmpty() && m.isNamed()) { |
| throw new IllegalArgumentException( |
| "Unnamed package cannot be added to " + m); |
| } |
| |
| if (m.isNamed()) { |
| if (!m.getDescriptor().packages().contains(proxyPkg)) { |
| throw new InternalError(proxyPkg + " not exist in " + m.getName()); |
| } |
| } |
| |
| /* |
| * Choose a name for the proxy class to generate. |
| */ |
| long num = nextUniqueNumber.getAndIncrement(); |
| String proxyName = proxyPkg.isEmpty() |
| ? proxyClassNamePrefix + num |
| : proxyPkg + "." + proxyClassNamePrefix + num; |
| |
| ClassLoader loader = getLoader(m); |
| trace(proxyName, m, loader, interfaces); |
| |
| /* |
| * Generate the specified proxy class. |
| */ |
| byte[] proxyClassFile = ProxyGenerator.generateProxyClass( |
| proxyName, interfaces.toArray(EMPTY_CLASS_ARRAY), accessFlags); |
| try { |
| Class<?> pc = UNSAFE.defineClass(proxyName, proxyClassFile, |
| 0, proxyClassFile.length, |
| loader, null); |
| reverseProxyCache.sub(pc).putIfAbsent(loader, Boolean.TRUE); |
| return pc; |
| } catch (ClassFormatError e) { |
| /* |
| * A ClassFormatError here means that (barring bugs in the |
| * proxy class generation code) there was some other |
| * invalid aspect of the arguments supplied to the proxy |
| * class creation (such as virtual machine limitations |
| * exceeded). |
| */ |
| throw new IllegalArgumentException(e.toString()); |
| } |
| } |
| |
| /** |
| * Test if given class is a class defined by |
| * {@link #defineProxyClass(Module, List)} |
| */ |
| static boolean isProxyClass(Class<?> c) { |
| return Objects.equals(reverseProxyCache.sub(c).get(c.getClassLoader()), |
| Boolean.TRUE); |
| } |
| |
| private static boolean isExportedType(Class<?> c) { |
| String pn = c.getPackageName(); |
| return Modifier.isPublic(c.getModifiers()) && c.getModule().isExported(pn); |
| } |
| |
| private static boolean isPackagePrivateType(Class<?> c) { |
| return !Modifier.isPublic(c.getModifiers()); |
| } |
| |
| private static String toDetails(Class<?> c) { |
| String access = "unknown"; |
| if (isExportedType(c)) { |
| access = "exported"; |
| } else if (isPackagePrivateType(c)) { |
| access = "package-private"; |
| } else { |
| access = "module-private"; |
| } |
| ClassLoader ld = c.getClassLoader(); |
| return String.format(" %s/%s %s loader %s", |
| c.getModule().getName(), c.getName(), access, ld); |
| } |
| |
| static void trace(String cn, |
| Module module, |
| ClassLoader loader, |
| List<Class<?>> interfaces) { |
| if (isDebug()) { |
| System.err.format("PROXY: %s/%s defined by %s%n", |
| module.getName(), cn, loader); |
| } |
| if (isDebug("debug")) { |
| interfaces.stream() |
| .forEach(c -> System.out.println(toDetails(c))); |
| } |
| } |
| |
| private static final String DEBUG = |
| GetPropertyAction.privilegedGetProperty("jdk.proxy.debug", ""); |
| |
| private static boolean isDebug() { |
| return !DEBUG.isEmpty(); |
| } |
| private static boolean isDebug(String flag) { |
| return DEBUG.equals(flag); |
| } |
| |
| // ProxyBuilder instance members start here.... |
| |
| private final List<Class<?>> interfaces; |
| private final Module module; |
| ProxyBuilder(ClassLoader loader, List<Class<?>> interfaces) { |
| if (!VM.isModuleSystemInited()) { |
| throw new InternalError("Proxy is not supported until " |
| + "module system is fully initialized"); |
| } |
| if (interfaces.size() > 65535) { |
| throw new IllegalArgumentException("interface limit exceeded: " |
| + interfaces.size()); |
| } |
| |
| Set<Class<?>> refTypes = referencedTypes(loader, interfaces); |
| |
| // IAE if violates any restrictions specified in newProxyInstance |
| validateProxyInterfaces(loader, interfaces, refTypes); |
| |
| this.interfaces = interfaces; |
| this.module = mapToModule(loader, interfaces, refTypes); |
| assert getLoader(module) == loader; |
| } |
| |
| ProxyBuilder(ClassLoader loader, Class<?> intf) { |
| this(loader, Collections.singletonList(intf)); |
| } |
| |
| /** |
| * Generate a proxy class and return its proxy Constructor with |
| * accessible flag already set. If the target module does not have access |
| * to any interface types, IllegalAccessError will be thrown by the VM |
| * at defineClass time. |
| * |
| * Must call the checkProxyAccess method to perform permission checks |
| * before calling this. |
| */ |
| Constructor<?> build() { |
| Class<?> proxyClass = defineProxyClass(module, interfaces); |
| final Constructor<?> cons; |
| try { |
| cons = proxyClass.getConstructor(constructorParams); |
| } catch (NoSuchMethodException e) { |
| throw new InternalError(e.toString(), e); |
| } |
| AccessController.doPrivileged(new PrivilegedAction<Void>() { |
| public Void run() { |
| cons.setAccessible(true); |
| return null; |
| } |
| }); |
| return cons; |
| } |
| |
| /** |
| * Validate the given proxy interfaces and the given referenced types |
| * are visible to the defining loader. |
| * |
| * @throws IllegalArgumentException if it violates the restrictions |
| * specified in {@link Proxy#newProxyInstance} |
| */ |
| private static void validateProxyInterfaces(ClassLoader loader, |
| List<Class<?>> interfaces, |
| Set<Class<?>> refTypes) |
| { |
| Map<Class<?>, Boolean> interfaceSet = new IdentityHashMap<>(interfaces.size()); |
| for (Class<?> intf : interfaces) { |
| /* |
| * Verify that the class loader resolves the name of this |
| * interface to the same Class object. |
| */ |
| ensureVisible(loader, intf); |
| |
| /* |
| * Verify that the Class object actually represents an |
| * interface. |
| */ |
| if (!intf.isInterface()) { |
| throw new IllegalArgumentException(intf.getName() + " is not an interface"); |
| } |
| |
| /* |
| * Verify that this interface is not a duplicate. |
| */ |
| if (interfaceSet.put(intf, Boolean.TRUE) != null) { |
| throw new IllegalArgumentException("repeated interface: " + intf.getName()); |
| } |
| } |
| |
| for (Class<?> type : refTypes) { |
| ensureVisible(loader, type); |
| } |
| } |
| |
| /* |
| * Returns all types referenced by all public non-static method signatures of |
| * the proxy interfaces |
| */ |
| private static Set<Class<?>> referencedTypes(ClassLoader loader, |
| List<Class<?>> interfaces) { |
| return interfaces.stream() |
| .flatMap(intf -> Stream.of(intf.getMethods()) |
| .filter(m -> !Modifier.isStatic(m.getModifiers())) |
| .flatMap(ProxyBuilder::methodRefTypes) |
| .map(ProxyBuilder::getElementType) |
| .filter(t -> !t.isPrimitive())) |
| .collect(Collectors.toSet()); |
| } |
| |
| /* |
| * Extracts all types referenced on a method signature including |
| * its return type, parameter types, and exception types. |
| */ |
| private static Stream<Class<?>> methodRefTypes(Method m) { |
| return Stream.of(new Class<?>[] { m.getReturnType() }, |
| m.getParameterTypes(), |
| m.getExceptionTypes()) |
| .flatMap(Stream::of); |
| } |
| |
| /** |
| * Returns the module that the generated proxy class belongs to. |
| * |
| * If all proxy interfaces are public and in exported packages, |
| * then the proxy class is in unnamed module. |
| * |
| * If any of proxy interface is package-private, then the proxy class |
| * is in the same module of the package-private interface. |
| * |
| * If all proxy interfaces are public and at least one in a non-exported |
| * package, then the proxy class is in a dynamic module in a |
| * non-exported package. Reads edge and qualified exports are added |
| * for dynamic module to access. |
| */ |
| private static Module mapToModule(ClassLoader loader, |
| List<Class<?>> interfaces, |
| Set<Class<?>> refTypes) { |
| Map<Class<?>, Module> modulePrivateTypes = new HashMap<>(); |
| Map<Class<?>, Module> packagePrivateTypes = new HashMap<>(); |
| for (Class<?> intf : interfaces) { |
| Module m = intf.getModule(); |
| if (Modifier.isPublic(intf.getModifiers())) { |
| // module-private types |
| if (!m.isExported(intf.getPackageName())) { |
| modulePrivateTypes.put(intf, m); |
| } |
| } else { |
| packagePrivateTypes.put(intf, m); |
| } |
| } |
| |
| // all proxy interfaces are public and exported, the proxy class |
| // is in unnamed module. Such proxy class is accessible to |
| // any unnamed module and named module that can read unnamed module |
| if (packagePrivateTypes.isEmpty() && modulePrivateTypes.isEmpty()) { |
| return loader != null ? loader.getUnnamedModule() |
| : BootLoader.getUnnamedModule(); |
| } |
| |
| if (packagePrivateTypes.size() > 0) { |
| // all package-private types must be in the same runtime package |
| // i.e. same package name and same module (named or unnamed) |
| // |
| // Configuration will fail if M1 and in M2 defined by the same loader |
| // and both have the same package p (so no need to check class loader) |
| if (packagePrivateTypes.size() > 1 && |
| (packagePrivateTypes.keySet().stream() // more than one package |
| .map(Class::getPackageName).distinct().count() > 1 || |
| packagePrivateTypes.values().stream() // or more than one module |
| .distinct().count() > 1)) { |
| throw new IllegalArgumentException( |
| "non-public interfaces from different packages"); |
| } |
| |
| // all package-private types are in the same module (named or unnamed) |
| Module target = null; |
| for (Module m : packagePrivateTypes.values()) { |
| if (getLoader(m) != loader) { |
| // the specified loader is not the same class loader |
| // of the non-public interface |
| throw new IllegalArgumentException( |
| "non-public interface is not defined by the given loader"); |
| } |
| target = m; |
| } |
| |
| // validate if the target module can access all other interfaces |
| for (Class<?> intf : interfaces) { |
| Module m = intf.getModule(); |
| if (m == target) continue; |
| |
| if (!target.canRead(m) || !m.isExported(intf.getPackageName(), target)) { |
| throw new IllegalArgumentException(target + " can't access " + intf.getName()); |
| } |
| } |
| |
| // return the module of the package-private interface |
| return target; |
| } |
| |
| // All proxy interfaces are public and at least one in a non-exported |
| // package. So maps to a dynamic proxy module and add reads edge |
| // and qualified exports, if necessary |
| Module target = getDynamicModule(loader); |
| |
| // set up proxy class access to proxy interfaces and types |
| // referenced in the method signature |
| Set<Class<?>> types = new HashSet<>(interfaces); |
| types.addAll(refTypes); |
| for (Class<?> c : types) { |
| ensureAccess(target, c); |
| } |
| return target; |
| } |
| |
| /* |
| * Ensure the given module can access the given class. |
| */ |
| private static void ensureAccess(Module target, Class<?> c) { |
| Module m = c.getModule(); |
| // add read edge and qualified export for the target module to access |
| if (!target.canRead(m)) { |
| Modules.addReads(target, m); |
| } |
| String pn = c.getPackageName(); |
| if (!m.isExported(pn, target)) { |
| Modules.addExports(m, pn, target); |
| } |
| } |
| |
| /* |
| * Ensure the given class is visible to the class loader. |
| */ |
| private static void ensureVisible(ClassLoader ld, Class<?> c) { |
| Class<?> type = null; |
| try { |
| type = Class.forName(c.getName(), false, ld); |
| } catch (ClassNotFoundException e) { |
| } |
| if (type != c) { |
| throw new IllegalArgumentException(c.getName() + |
| " referenced from a method is not visible from class loader"); |
| } |
| } |
| |
| private static Class<?> getElementType(Class<?> type) { |
| Class<?> e = type; |
| while (e.isArray()) { |
| e = e.getComponentType(); |
| } |
| return e; |
| } |
| |
| private static final ClassLoaderValue<Module> dynProxyModules = |
| new ClassLoaderValue<>(); |
| private static final AtomicInteger counter = new AtomicInteger(); |
| |
| /* |
| * Define a dynamic module for the generated proxy classes in |
| * a non-exported package named com.sun.proxy.$MODULE. |
| * |
| * Each class loader will have one dynamic module. |
| */ |
| private static Module getDynamicModule(ClassLoader loader) { |
| return dynProxyModules.computeIfAbsent(loader, (ld, clv) -> { |
| // create a dynamic module and setup module access |
| String mn = "jdk.proxy" + counter.incrementAndGet(); |
| String pn = PROXY_PACKAGE_PREFIX + "." + mn; |
| ModuleDescriptor descriptor = |
| ModuleDescriptor.newModule(mn, Set.of(SYNTHETIC)) |
| .packages(Set.of(pn)) |
| .build(); |
| Module m = Modules.defineModule(ld, descriptor, null); |
| Modules.addReads(m, Proxy.class.getModule()); |
| // java.base to create proxy instance |
| Modules.addExports(m, pn, Object.class.getModule()); |
| return m; |
| }); |
| } |
| } |
| |
| /** |
| * Returns a proxy instance for the specified interfaces |
| * that dispatches method invocations to the specified invocation |
| * handler. |
| * <p> |
| * <a id="restrictions">{@code IllegalArgumentException} will be thrown |
| * if any of the following restrictions is violated:</a> |
| * <ul> |
| * <li>All of {@code Class} objects in the given {@code interfaces} array |
| * must represent interfaces, not classes or primitive types. |
| * |
| * <li>No two elements in the {@code interfaces} array may |
| * refer to identical {@code Class} objects. |
| * |
| * <li>All of the interface types must be visible by name through the |
| * specified class loader. In other words, for class loader |
| * {@code cl} and every interface {@code i}, the following |
| * expression must be true:<p> |
| * {@code Class.forName(i.getName(), false, cl) == i} |
| * |
| * <li>All of the types referenced by all |
| * public method signatures of the specified interfaces |
| * and those inherited by their superinterfaces |
| * must be visible by name through the specified class loader. |
| * |
| * <li>All non-public interfaces must be in the same package |
| * and module, defined by the specified class loader and |
| * the module of the non-public interfaces can access all of |
| * the interface types; otherwise, it would not be possible for |
| * the proxy class to implement all of the interfaces, |
| * regardless of what package it is defined in. |
| * |
| * <li>For any set of member methods of the specified interfaces |
| * that have the same signature: |
| * <ul> |
| * <li>If the return type of any of the methods is a primitive |
| * type or void, then all of the methods must have that same |
| * return type. |
| * <li>Otherwise, one of the methods must have a return type that |
| * is assignable to all of the return types of the rest of the |
| * methods. |
| * </ul> |
| * |
| * <li>The resulting proxy class must not exceed any limits imposed |
| * on classes by the virtual machine. For example, the VM may limit |
| * the number of interfaces that a class may implement to 65535; in |
| * that case, the size of the {@code interfaces} array must not |
| * exceed 65535. |
| * </ul> |
| * |
| * <p>Note that the order of the specified proxy interfaces is |
| * significant: two requests for a proxy class with the same combination |
| * of interfaces but in a different order will result in two distinct |
| * proxy classes. |
| * |
| * @param loader the class loader to define the proxy class |
| * @param interfaces the list of interfaces for the proxy class |
| * to implement |
| * @param h the invocation handler to dispatch method invocations to |
| * @return a proxy instance with the specified invocation handler of a |
| * proxy class that is defined by the specified class loader |
| * and that implements the specified interfaces |
| * @throws IllegalArgumentException if any of the <a href="#restrictions"> |
| * restrictions</a> on the parameters are violated |
| * @throws SecurityException if a security manager, <em>s</em>, is present |
| * and any of the following conditions is met: |
| * <ul> |
| * <li> the given {@code loader} is {@code null} and |
| * the caller's class loader is not {@code null} and the |
| * invocation of {@link SecurityManager#checkPermission |
| * s.checkPermission} with |
| * {@code RuntimePermission("getClassLoader")} permission |
| * denies access;</li> |
| * <li> for each proxy interface, {@code intf}, |
| * the caller's class loader is not the same as or an |
| * ancestor of the class loader for {@code intf} and |
| * invocation of {@link SecurityManager#checkPackageAccess |
| * s.checkPackageAccess()} denies access to {@code intf};</li> |
| * <li> any of the given proxy interfaces is non-public and the |
| * caller class is not in the same {@linkplain Package runtime package} |
| * as the non-public interface and the invocation of |
| * {@link SecurityManager#checkPermission s.checkPermission} with |
| * {@code ReflectPermission("newProxyInPackage.{package name}")} |
| * permission denies access.</li> |
| * </ul> |
| * @throws NullPointerException if the {@code interfaces} array |
| * argument or any of its elements are {@code null}, or |
| * if the invocation handler, {@code h}, is |
| * {@code null} |
| * |
| * @see <a href="#membership">Package and Module Membership of Proxy Class</a> |
| * @revised 9 |
| * @spec JPMS |
| */ |
| @CallerSensitive |
| public static Object newProxyInstance(ClassLoader loader, |
| Class<?>[] interfaces, |
| InvocationHandler h) { |
| Objects.requireNonNull(h); |
| |
| final Class<?> caller = System.getSecurityManager() == null |
| ? null |
| : Reflection.getCallerClass(); |
| |
| /* |
| * Look up or generate the designated proxy class and its constructor. |
| */ |
| Constructor<?> cons = getProxyConstructor(caller, loader, interfaces); |
| |
| return newProxyInstance(caller, cons, h); |
| } |
| |
| private static Object newProxyInstance(Class<?> caller, // null if no SecurityManager |
| Constructor<?> cons, |
| InvocationHandler h) { |
| /* |
| * Invoke its constructor with the designated invocation handler. |
| */ |
| try { |
| if (caller != null) { |
| checkNewProxyPermission(caller, cons.getDeclaringClass()); |
| } |
| |
| return cons.newInstance(new Object[]{h}); |
| } catch (IllegalAccessException | InstantiationException e) { |
| throw new InternalError(e.toString(), e); |
| } catch (InvocationTargetException e) { |
| Throwable t = e.getCause(); |
| if (t instanceof RuntimeException) { |
| throw (RuntimeException) t; |
| } else { |
| throw new InternalError(t.toString(), t); |
| } |
| } |
| } |
| |
| private static void checkNewProxyPermission(Class<?> caller, Class<?> proxyClass) { |
| SecurityManager sm = System.getSecurityManager(); |
| if (sm != null) { |
| if (ReflectUtil.isNonPublicProxyClass(proxyClass)) { |
| ClassLoader ccl = caller.getClassLoader(); |
| ClassLoader pcl = proxyClass.getClassLoader(); |
| |
| // do permission check if the caller is in a different runtime package |
| // of the proxy class |
| int n = proxyClass.getName().lastIndexOf('.'); |
| String pkg = (n == -1) ? "" : proxyClass.getName().substring(0, n); |
| |
| n = caller.getName().lastIndexOf('.'); |
| String callerPkg = (n == -1) ? "" : caller.getName().substring(0, n); |
| |
| if (pcl != ccl || !pkg.equals(callerPkg)) { |
| sm.checkPermission(new ReflectPermission("newProxyInPackage." + pkg)); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Returns the class loader for the given module. |
| */ |
| private static ClassLoader getLoader(Module m) { |
| PrivilegedAction<ClassLoader> pa = m::getClassLoader; |
| return AccessController.doPrivileged(pa); |
| } |
| |
| /** |
| * Returns true if the given class is a proxy class. |
| * |
| * @implNote The reliability of this method is important for the ability |
| * to use it to make security decisions, so its implementation should |
| * not just test if the class in question extends {@code Proxy}. |
| * |
| * @param cl the class to test |
| * @return {@code true} if the class is a proxy class and |
| * {@code false} otherwise |
| * @throws NullPointerException if {@code cl} is {@code null} |
| * |
| * @revised 9 |
| * @spec JPMS |
| */ |
| public static boolean isProxyClass(Class<?> cl) { |
| return Proxy.class.isAssignableFrom(cl) && ProxyBuilder.isProxyClass(cl); |
| } |
| |
| /** |
| * 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; |
| } |
| |
| private static final Class<?>[] EMPTY_CLASS_ARRAY = new Class<?>[0]; |
| private static final String PROXY_PACKAGE_PREFIX = ReflectUtil.PROXY_PACKAGE; |
| } |
