1: public abstract class AbstractProxyFactory implements ProxyFactory {
 2: 
 3:     public <T> T getProxy(Invoker<T> invoker) throws RpcException {
 4:         Class<?>[] interfaces = null;
 5:         // TODO 8022 芋艿
 6:         String config = invoker.getUrl().getParameter("interfaces");
 7:         if (config != null && config.length() > 0) {
 8:             String[] types = Constants.COMMA_SPLIT_PATTERN.split(config);
 9:             if (types != null && types.length > 0) {
10:                 interfaces = new Class<?>[types.length + 2];
11:                 interfaces[0] = invoker.getInterface();
12:                 interfaces[1] = EchoService.class;
13:                 for (int i = 0; i < types.length; i++) {
14:                     interfaces[i + 1] = ReflectUtils.forName(types[i]);
15:                 }
16:             }
17:         }
18:         // 增加 EchoService 接口，用于回生测试。参见文档《回声测试》http://dubbo.apache.org/zh-cn/docs/user/demos/echo-service.html
19:         if (interfaces == null) {
20:             interfaces = new Class<?>[]{invoker.getInterface(), EchoService.class};
21:         }
22:         return getProxy(invoker, interfaces);
23:     }
24: 
25:     public abstract <T> T getProxy(Invoker<T> invoker, Class<?>[] types);
26: 
27: }

 1: public class JavassistProxyFactory extends AbstractProxyFactory {
 2: 
 3:     @SuppressWarnings("unchecked")
 4:     public <T> T getProxy(Invoker<T> invoker, Class<?>[] interfaces) {
 5:         return (T) Proxy.getProxy(interfaces).newInstance(new InvokerInvocationHandler(invoker));
 6:     }
 7: 
 8:     public <T> Invoker<T> getInvoker(T proxy, Class<T> type, URL url) {
 9:         // TODO Wrapper cannot handle this scenario correctly: the classname contains '$'
10:         // TODO Wrapper类不能正确处理带$的类名
11:         final Wrapper wrapper = Wrapper.getWrapper(proxy.getClass().getName().indexOf('$') < 0 ? proxy.getClass() : type);
12:         return new AbstractProxyInvoker<T>(proxy, type, url) {
13:             @Override
14:             protected Object doInvoke(T proxy, String methodName,
15:                                       Class<?>[] parameterTypes,
16:                                       Object[] arguments) throws Throwable {
17:                 return wrapper.invokeMethod(proxy, methodName, parameterTypes, arguments);
18:             }
19:         };
20:     }
21: 
22: }

 1: public class InvokerInvocationHandler implements InvocationHandler {
 2: 
 3:     /**
 4:      * Invoker 对象
 5:      */
 6:     private final Invoker<?> invoker;
 7: 
 8:     public InvokerInvocationHandler(Invoker<?> handler) {
 9:         this.invoker = handler;
10:     }
11: 
12:     @Override public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
13:         String methodName = method.getName();
14:         Class<?>[] parameterTypes = method.getParameterTypes();
15:         // wait 等方法，直接反射调用
16:         if (method.getDeclaringClass() == Object.class) {
17:             return method.invoke(invoker, args);
18:         }
19:         // 基础方法，不使用 RPC 调用
20:         if ("toString".equals(methodName) && parameterTypes.length == 0) {
21:             return invoker.toString();
22:         }
23:         if ("hashCode".equals(methodName) && parameterTypes.length == 0) {
24:             return invoker.hashCode();
25:         }
26:         if ("equals".equals(methodName) && parameterTypes.length == 1) {
27:             return invoker.equals(args[0]);
28:         }
29:         // RPC 调用
30:         return invoker.invoke(new RpcInvocation(method, args)).recreate();
31:     }
32: 
33: }

/**
 * 代理的对象，一般是 Service 实现对象
 */
private final T proxy;
/**
 * 接口类型，一般是 Service 接口
 */
private final Class<T> type;
/**
 * URL 对象，一般是暴露服务的 URL 对象
 */
private final URL url;

public AbstractProxyInvoker(T proxy, Class<T> type, URL url) {
    if (proxy == null) {
        throw new IllegalArgumentException("proxy == null");
    }
    if (type == null) {
        throw new IllegalArgumentException("interface == null");
    }
    if (!type.isInstance(proxy)) { //
        throw new IllegalArgumentException(proxy.getClass().getName() + " not implement interface " + type);
    }
    this.proxy = proxy;
    this.type = type;
    this.url = url;
}

1: public Result invoke(Invocation invocation) throws RpcException {
2:     try {
3:         return new RpcResult(doInvoke(proxy, invocation.getMethodName(), invocation.getParameterTypes(), invocation.getArguments()));
4:     } catch (InvocationTargetException e) {
5:         return new RpcResult(e.getTargetException());
6:     } catch (Throwable e) {
7:         throw new RpcException("Failed to invoke remote proxy method " + invocation.getMethodName() + " to " + getUrl() + ", cause: " + e.getMessage(), e);
8:     }
9: }

public class Proxy0 extends Proxy implements ClassGenerator.DC {
    
    public Object newInstance(InvocationHandler paramInvocationHandler) {
        return new proxy0(paramInvocationHandler);
    }
    
}

abstract public String[] getPropertyNames();
abstract public Class<?> getPropertyType(String pn);

abstract public boolean hasProperty(String name);
abstract public Object getPropertyValue(Object instance, String pn) throws NoSuchPropertyException, IllegalArgumentException;
abstract public void setPropertyValue(Object instance, String pn, Object pv) throws NoSuchPropertyException, IllegalArgumentException;

abstract public String[] getMethodNames();
abstract public String[] getDeclaredMethodNames();

/**
 * invoke method.
 *
 * 调用方法
 *
 * @param instance instance.
 *                 被调用的对象
 * @param mn       method name.
 *                 方法名
 * @param types 参数类型数组
 * @param args     argument array.
 *                 参数数组
 * @return return value.
 *                  返回值
 */
abstract public Object invokeMethod(Object instance, String mn, Class<?>[] types, Object[] args) throws NoSuchMethodException, InvocationTargetException;

 1: public static Wrapper getWrapper(Class<?> c) {
 2:     // 判断是否继承 ClassGenerator.DC.class ，如果是，拿到父类，避免重复包装
 3:     while (ClassGenerator.isDynamicClass(c)) // can not wrapper on dynamic class.
 4:         c = c.getSuperclass();
 5: 
 6:     // 指定类为 Object.class
 7:     if (c == Object.class)
 8:         return OBJECT_WRAPPER;
 9: 
10:     // 从缓存中获得 Wrapper 对象
11:     Wrapper ret = WRAPPER_MAP.get(c);
12:     // 创建 Wrapper 对象，并添加到缓存
13:     if (ret == null) {
14:         ret = makeWrapper(c);
15:         WRAPPER_MAP.put(c, ret);
16:     }
17:     return ret;
18: }

  1: private static Wrapper makeWrapper(Class<?> c) {
  2:     // 非私有类
  3:     if (c.isPrimitive())
  4:         throw new IllegalArgumentException("Can not create wrapper for primitive type: " + c);
  5: 
  6:     // 类名
  7:     String name = c.getName();
  8:     // 类加载器
  9:     ClassLoader cl = ClassHelper.getClassLoader(c);
 10: 
 11:     // 设置属性方法 `#setPropertyValue(o, n, v)` 的开头的代码
 12:     StringBuilder c1 = new StringBuilder("public void setPropertyValue(Object o, String n, Object v){ ");
 13:     // 获得属性方法 `#getPropertyValue(o, n)` 的开头的代码
 14:     StringBuilder c2 = new StringBuilder("public Object getPropertyValue(Object o, String n){ ");
 15:     // 调用方法 `#invokeMethod(o, n, p, v)` 的开头的代码
 16:     StringBuilder c3 = new StringBuilder("public Object invokeMethod(Object o, String n, Class[] p, Object[] v) throws " + InvocationTargetException.class.getName() + "{ ");
 17: 
 18:     // 添加每个方法的，被调用对象的类型转换的代码
 19:     c1.append(name).append(" w; try{ w = ((").append(name).append(")$1); }catch(Throwable e){ throw new IllegalArgumentException(e); }");
 20:     c2.append(name).append(" w; try{ w = ((").append(name).append(")$1); }catch(Throwable e){ throw new IllegalArgumentException(e); }");
 21:     c3.append(name).append(" w; try{ w = ((").append(name).append(")$1); }catch(Throwable e){ throw new IllegalArgumentException(e); }");
 22: 
 23:     // 属性名与属性名的集合，用于 `#hasProperty(...)` `#setPropertyValue(...)` `getPropertyValue(...)` 方法。
 24:     Map<String, Class<?>> pts = new HashMap<String, Class<?>>(); // <property name, property types>
 25:     // 方法签名与方法对象的集合，用于 `#invokeMethod(..)` 方法。
 26:     Map<String, Method> ms = new LinkedHashMap<String, Method>(); // <method desc, Method instance>
 27:     // 方法名数组用于 `#getMethodNames()` 方法。
 28:     List<String> mns = new ArrayList<String>(); // method names.
 29:     // 定义的方法名数组，用于 `#getDeclaredMethodNames()` 方法。
 30:     List<String> dmns = new ArrayList<String>(); // declaring method names.
 31: 
 32:     // 循环 public 属性，添加每个属性的设置和获得分别到 `#setPropertyValue(o, n, v)` 和 `#getPropertyValue(o, n)` 的代码
 33:     // get all public field.
 34:     for (Field f : c.getFields()) {
 35:         String fn = f.getName();
 36:         Class<?> ft = f.getType();
 37:         if (Modifier.isStatic(f.getModifiers()) || Modifier.isTransient(f.getModifiers())) // 排除 static 和 transient
 38:             continue;
 39: 
 40:         c1.append(" if( $2.equals(\"").append(fn).append("\") ){ w.").append(fn).append("=").append(arg(ft, "$3")).append("; return; }");
 41:         c2.append(" if( $2.equals(\"").append(fn).append("\") ){ return ($w)w.").append(fn).append("; }");
 42:         // 添加到 `pts` 中
 43:         pts.put(fn, ft);
 44:     }
 45: 
 46:     Method[] methods = c.getMethods();
 47:     // 如果有方法，添加 `#invokeMethod(o, n, p, v)` 的 try 的代码
 48:     // get all public method.
 49:     boolean hasMethod = hasMethods(methods);
 50:     if (hasMethod) {
 51:         c3.append(" try{");
 52:     }
 53:     for (Method m : methods) {
 54:         // 跳过来自 Object 的内置方法
 55:         if (m.getDeclaringClass() == Object.class) //ignore Object's method.
 56:             continue;
 57: 
 58:         String mn = m.getName(); // 方法名
 59:         // 使用方法名 + 方法参数长度来判断
 60:         c3.append(" if( \"").append(mn).append("\".equals( $2 ) ");
 61:         int len = m.getParameterTypes().length;
 62:         c3.append(" && ").append(" $3.length == ").append(len);
 63: 
 64:         // 若相同方法名存在多个，增加参数类型数组的比较判断
 65:         boolean override = false;
 66:         for (Method m2 : methods) {
 67:             if (m != m2 && m.getName().equals(m2.getName())) {
 68:                 override = true;
 69:                 break;
 70:             }
 71:         }
 72:         if (override) {
 73:             if (len > 0) {
 74:                 for (int l = 0; l < len; l++) {
 75:                     c3.append(" && ").append(" $3[").append(l).append("].getName().equals(\"")
 76:                             .append(m.getParameterTypes()[l].getName()).append("\")");
 77:                 }
 78:             }
 79:         }
 80: 
 81:         c3.append(" ) { ");
 82: 
 83:         // 添加调用对象的对应方法的代码
 84:         if (m.getReturnType() == Void.TYPE)
 85:             c3.append(" w.").append(mn).append('(').append(args(m.getParameterTypes(), "$4")).append(");").append(" return null;");
 86:         else
 87:             c3.append(" return ($w)w.").append(mn).append('(').append(args(m.getParameterTypes(), "$4")).append(");");
 88: 
 89:         c3.append(" }");
 90: 
 91:         // 添加到 `mns` 中
 92:         mns.add(mn);
 93:         // 添加到 `dmns` 中
 94:         if (m.getDeclaringClass() == c)
 95:             dmns.add(mn);
 96:         // 添加到 `ms` 中
 97:         ms.put(ReflectUtils.getDesc(m), m);
 98:     }
 99:     // 如果有方法，添加 `#invokeMethod(o, n, p, v)` 的 catch 的代码
100:     if (hasMethod) {
101:         c3.append(" } catch(Throwable e) { ");
102:         c3.append("     throw new java.lang.reflect.InvocationTargetException(e); ");
103:         c3.append(" }");
104:     }
105:     // 添加 `#invokeMethod(o, n, p, v)` 的未匹配到方法的代码
106:     c3.append(" throw new " + NoSuchMethodException.class.getName() + "(\"Not found method \\\"\"+$2+\"\\\" in class " + c.getName() + ".\"); }");
107: 
108:     // 循环 setting/getting 方法，添加每个属性的设置和获得分别到 `#setPropertyValue(o, n, v)` 和 `#getPropertyValue(o, n)` 的代码
109:     // deal with get/set method.
110:     Matcher matcher;
111:     for (Map.Entry<String, Method> entry : ms.entrySet()) {
112:         String md = entry.getKey();
113:         Method method = entry.getValue();
114:         if ((matcher = ReflectUtils.GETTER_METHOD_DESC_PATTERN.matcher(md)).matches()) {
115:             String pn = propertyName(matcher.group(1));
116:             c2.append(" if( $2.equals(\"").append(pn).append("\") ){ return ($w)w.").append(method.getName()).append("(); }");
117:             // 添加到 `pts` 中
118:             pts.put(pn, method.getReturnType());
119:         } else if ((matcher = ReflectUtils.IS_HAS_CAN_METHOD_DESC_PATTERN.matcher(md)).matches()) {
120:             String pn = propertyName(matcher.group(1));
121:             c2.append(" if( $2.equals(\"").append(pn).append("\") ){ return ($w)w.").append(method.getName()).append("(); }");
122:             // 添加到 `pts` 中
123:             pts.put(pn, method.getReturnType());
124:         } else if ((matcher = ReflectUtils.SETTER_METHOD_DESC_PATTERN.matcher(md)).matches()) { // 不支持 public T setName(String name) { this.name = name; return this;} 这种返回 this 的形式。
125:             Class<?> pt = method.getParameterTypes()[0];
126:             String pn = propertyName(matcher.group(1));
127:             c1.append(" if( $2.equals(\"").append(pn).append("\") ){ w.").append(method.getName()).append("(").append(arg(pt, "$3")).append("); return; }");
128:             // 添加到 `pts` 中
129:             pts.put(pn, pt);
130:         }
131:     }
132:     c1.append(" throw new " + NoSuchPropertyException.class.getName() + "(\"Not found property \\\"\"+$2+\"\\\" filed or setter method in class " + c.getName() + ".\"); }");
133:     c2.append(" throw new " + NoSuchPropertyException.class.getName() + "(\"Not found property \\\"\"+$2+\"\\\" filed or setter method in class " + c.getName() + ".\"); }");
134: 
135:     // make class
136:     long id = WRAPPER_CLASS_COUNTER.getAndIncrement();
137:     // 创建 ClassGenerator 对象
138:     ClassGenerator cc = ClassGenerator.newInstance(cl);
139:     // 设置类名
140:     cc.setClassName((Modifier.isPublic(c.getModifiers()) ? Wrapper.class.getName() : c.getName() + "$sw") + id);
141:     // 设置父类为 Wrapper.class
142:     cc.setSuperClass(Wrapper.class);
143: 
144:     // 添加构造方法，参数 空
145:     cc.addDefaultConstructor();
146:     // 添加静态属性 `pns` 的代码
147:     cc.addField("public static String[] pns;"); // property name array.
148:     // 添加静态属性 `pts` 的代码
149:     cc.addField("public static " + Map.class.getName() + " pts;"); // property type map.
150:     // 添加静态属性 `pts` 的代码
151:     cc.addField("public static String[] mns;"); // all method name array.
152:     // 添加静态属性 `dmns` 的代码
153:     cc.addField("public static String[] dmns;"); // declared method name array.
154:     // 添加静态属性 `mts` 的代码。每个方法的参数数组。
155:     for (int i = 0, len = ms.size(); i < len; i++)
156:         cc.addField("public static Class[] mts" + i + ";");
157: 
158:     // ======= 添加抽象方法的实现，到 `cc` 中
159:     // 添加 `#getPropertyNames()` 的代码到 `cc`
160:     cc.addMethod("public String[] getPropertyNames(){ return pns; }");
161:     // 添加 `#hasProperty(n)` 的代码到 `cc`
162:     cc.addMethod("public boolean hasProperty(String n){ return pts.containsKey($1); }");
163:     // 添加 `#getPropertyType(n)` 的代码到 `cc`
164:     cc.addMethod("public Class getPropertyType(String n){ return (Class)pts.get($1); }");
165:     // 添加 `#getMethodNames()` 的代码到 `cc`
166:     cc.addMethod("public String[] getMethodNames(){ return mns; }");
167:     // 添加 `#getDeclaredMethodNames()` 的代码到 `cc`
168:     cc.addMethod("public String[] getDeclaredMethodNames(){ return dmns; }");
169:     // 添加 `#setPropertyValue(o, n, v)` 的代码到 `cc`
170:     cc.addMethod(c1.toString());
171:     // 添加 `#getPropertyValue(o, n)` 的代码到 `cc`
172:     cc.addMethod(c2.toString());
173:     // 添加 `#invokeMethod(o, n, p, v)` 的代码到 `cc`
174:     cc.addMethod(c3.toString());
175: 
176:     try {
177:         // 生成类
178:         Class<?> wc = cc.toClass();
179:         // 反射，设置静态变量的值
180:         // setup static field.
181:         wc.getField("pts").set(null, pts);
182:         wc.getField("pns").set(null, pts.keySet().toArray(new String[0]));
183:         wc.getField("mns").set(null, mns.toArray(new String[0]));
184:         wc.getField("dmns").set(null, dmns.toArray(new String[0]));
185:         int ix = 0;
186:         for (Method m : ms.values())
187:             wc.getField("mts" + ix++).set(null, m.getParameterTypes());
188:         // 创建对象
189:         return (Wrapper) wc.newInstance();
190:     } catch (RuntimeException e) {
191:         throw e;
192:     } catch (Throwable e) {
193:         throw new RuntimeException(e.getMessage(), e);
194:     } finally {
195:         // 释放资源
196:         cc.release();
197:         ms.clear();
198:         mns.clear();
199:         dmns.clear();
200:     }
201: }