Dubbo Wrapper

private static Wrapper makeWrapper(Class<?> c) {
    String name = c.getName();
    ClassLoader cl = ClassUtils.getClassLoader(c);
    StringBuilder c1 = new StringBuilder("public void setPropertyValue(Object o, String n, Object v){ ");
    StringBuilder c2 = new StringBuilder("public Object getPropertyValue(Object o, String n){ ");
    StringBuilder c3 = new StringBuilder("public Object invokeMethod(Object o, String n, Class[] p, Object[] v) throws " + InvocationTargetException.class.getName() + "{ ");
    c1.append(name).append(" w; try{ w = ((").append(name).append(")$1); }catch(Throwable e){ throw new IllegalArgumentException(e); }");
    c2.append(name).append(" w; try{ w = ((").append(name).append(")$1); }catch(Throwable e){ throw new IllegalArgumentException(e); }");
    c3.append(name).append(" w; try{ w = ((").append(name).append(")$1); }catch(Throwable e){ throw new IllegalArgumentException(e); }");
    Map<String, Class<?>> pts = new HashMap<>(); // <property name, property types>
    Map<String, Method> ms = new LinkedHashMap<>(); // <method desc, Method instance>
    List<String> mns = new ArrayList<>(); // method names.
    List<String> dmns = new ArrayList<>(); // declaring method names.
    // get all public field.
    for (Field f : c.getFields()) {
        String fn = f.getName();
        Class<?> ft = f.getType();
        if (Modifier.isStatic(f.getModifiers()) || Modifier.isTransient(f.getModifiers())) {
            continue;
        }
        c1.append(" if( $2.equals(\"").append(fn).append("\") ){ w.").append(fn).append("=").append(arg(ft, "$3")).append("; return; }");
        c2.append(" if( $2.equals(\"").append(fn).append("\") ){ return ($w)w.").append(fn).append("; }");
        pts.put(fn, ft);
    }
    Method[] methods = c.getMethods();
    // get all public method.
    boolean hasMethod = hasMethods(methods);
    if (hasMethod) {
        c3.append(" try{");
        for (Method m : methods) {
            //ignore Object's method.
            if (m.getDeclaringClass() == Object.class) {
                continue;
            }
            String mn = m.getName();
            c3.append(" if( \"").append(mn).append("\".equals( $2 ) ");
            int len = m.getParameterTypes().length;
            c3.append(" && ").append(" $3.length == ").append(len);
            boolean override = false;
            for (Method m2 : methods) {
                if (m != m2 && m.getName().equals(m2.getName())) {
                    override = true;
                    break;
                }
            }
            if (override) {
                if (len > 0) {
                    for (int l = 0; l < len; l++) {
                        c3.append(" && ").append(" $3[").append(l).append("].getName().equals(\"")
                                .append(m.getParameterTypes()[l].getName()).append("\")");
                    }
                }
            }
            c3.append(" ) { ");
            if (m.getReturnType() == Void.TYPE) {
                c3.append(" w.").append(mn).append('(').append(args(m.getParameterTypes(), "$4")).append(");").append(" return null;");
            } else {
                c3.append(" return ($w)w.").append(mn).append('(').append(args(m.getParameterTypes(), "$4")).append(");");
            }
            c3.append(" }");
            mns.add(mn);
            if (m.getDeclaringClass() == c) {
                dmns.add(mn);
            }
            ms.put(ReflectUtils.getDesc(m), m);
        }
        c3.append(" } catch(Throwable e) { ");
        c3.append("     throw new java.lang.reflect.InvocationTargetException(e); ");
        c3.append(" }");
    }
    c3.append(" throw new " + NoSuchMethodException.class.getName() + "(\"Not found method \\\"\"+$2+\"\\\" in class " + c.getName() + ".\"); }");
    // deal with get/set method.
    Matcher matcher;
    for (Map.Entry<String, Method> entry : ms.entrySet()) {
        String md = entry.getKey();
        Method method = entry.getValue();
        if ((matcher = ReflectUtils.GETTER_METHOD_DESC_PATTERN.matcher(md)).matches()) {
            String pn = propertyName(matcher.group(1));
            c2.append(" if( $2.equals(\"").append(pn).append("\") ){ return ($w)w.").append(method.getName()).append("(); }");
            pts.put(pn, method.getReturnType());
        } else if ((matcher = ReflectUtils.IS_HAS_CAN_METHOD_DESC_PATTERN.matcher(md)).matches()) {
            String pn = propertyName(matcher.group(1));
            c2.append(" if( $2.equals(\"").append(pn).append("\") ){ return ($w)w.").append(method.getName()).append("(); }");
            pts.put(pn, method.getReturnType());
        } else if ((matcher = ReflectUtils.SETTER_METHOD_DESC_PATTERN.matcher(md)).matches()) {
            Class<?> pt = method.getParameterTypes()[0];
            String pn = propertyName(matcher.group(1));
            c1.append(" if( $2.equals(\"").append(pn).append("\") ){ w.").append(method.getName()).append("(").append(arg(pt, "$3")).append("); return; }");
            pts.put(pn, pt);
        }
    }
    c1.append(" throw new " + NoSuchPropertyException.class.getName() + "(\"Not found property \\\"\"+$2+\"\\\" field or setter method in class " + c.getName() + ".\"); }");
    c2.append(" throw new " + NoSuchPropertyException.class.getName() + "(\"Not found property \\\"\"+$2+\"\\\" field or setter method in class " + c.getName() + ".\"); }");
    // make class
    long id = WRAPPER_CLASS_COUNTER.getAndIncrement();
    ClassGenerator cc = ClassGenerator.newInstance(cl);
    cc.setClassName((Modifier.isPublic(c.getModifiers()) ? Wrapper.class.getName() : c.getName() + "$sw") + id);
    cc.setSuperClass(Wrapper.class);
    cc.addDefaultConstructor();
    cc.addField("public static String[] pns;"); // property name array.
    cc.addField("public static " + Map.class.getName() + " pts;"); // property type map.
    cc.addField("public static String[] mns;"); // all method name array.
    cc.addField("public static String[] dmns;"); // declared method name array.
    for (int i = 0, len = ms.size(); i < len; i++) {
        cc.addField("public static Class[] mts" + i + ";");
    }
    cc.addMethod("public String[] getPropertyNames(){ return pns; }");
    cc.addMethod("public boolean hasProperty(String n){ return pts.containsKey($1); }");
    cc.addMethod("public Class getPropertyType(String n){ return (Class)pts.get($1); }");
    cc.addMethod("public String[] getMethodNames(){ return mns; }");
    cc.addMethod("public String[] getDeclaredMethodNames(){ return dmns; }");
    cc.addMethod(c1.toString());
    cc.addMethod(c2.toString());
    cc.addMethod(c3.toString());
    try {
        Class<?> wc = cc.toClass();
        // setup static field.
        wc.getField("pts").set(null, pts);
        wc.getField("pns").set(null, pts.keySet().toArray(new String[0]));
        wc.getField("mns").set(null, mns.toArray(new String[0]));
        wc.getField("dmns").set(null, dmns.toArray(new String[0]));
        int ix = 0;
        for (Method m : ms.values()) {
            wc.getField("mts" + ix++).set(null, m.getParameterTypes());
        }
        return (Wrapper) wc.newInstance();
    } catch (RuntimeException e) {
        throw e;
    } catch (Throwable e) {
        throw new RuntimeException(e.getMessage(), e);
    } finally {
        cc.release();
        ms.clear();
        mns.clear();
        dmns.clear();
    }
}
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public class TestWrapper {
    private String name;
    private Integer age;
    public String address;
    public String sayHi(){
        return "hi";
    }
    public String sayGoodbye() {
        return "bye";
    }
}
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package org.apache.dubbo.common.bytecode;
public class Wrapper0 extends Wrapper {
    /**
     * property name array.
     */
    public static String[] pns;
    /**
     * property type map.
     */
    public static Map pts;
    /**
     * all method name array.
     */
    public static String[] mns;
    /**
     * declared method name array.
     */
    public static String[] dmns;
    public static Class[] mts0; //存放方法的参数类型
    public static Class[] mts1; // 存放方法的参数类型
    public String[] getPropertyNames(){ return pns; }
    public boolean hasProperty(String n){ return pts.containsKey(n); }
    public Class getPropertyType(String n){ return (Class)pts.get(n); }
    public String[] getMethodNames(){ return mns; }
    public String[] getDeclaredMethodNames(){ return dmns; }
    public Object getPropertyValue(Object o, String n) {
        TestWrapper w;
        try {
            w = ((TestWrapper) $1);
        } catch (Throwable e) {
            throw new IllegalArgumentException(e);
        }
        if ($2.equals("address")) {
            return ($w) w.address;
        }
        throw new org.apache.dubbo.common.bytecode.NoSuchPropertyException("Not found property \"" + $2 + "\" field or setter method in class TestWrapper.");
    }
    public Object invokeMethod(Object o, String n, Class[] p, Object[] v) throws java.lang.reflect.InvocationTargetException {
        TestWrapper w;
        try {
            w = ((TestWrapper) $1);
        } catch (Throwable e) {
            throw new IllegalArgumentException(e);
        }
        try {
            if ("sayHi".equals($2) && $3.length == 0) {
                return ($w) w.sayHi();
            }
            if ("sayGoodbye".equals($2) && $3.length == 0) {
                return ($w) w.sayGoodbye();
            }
        } catch (Throwable e) {
            throw new java.lang.reflect.InvocationTargetException(e);
        }
        throw new org.apache.dubbo.common.bytecode.NoSuchMethodException("Not found method \"" + $2 + "\" in class TestWrapper.");
    }
    public void setPropertyValue(Object o, String n, Object v) {
        TestWrapper w;
        try {
            w = ((TestWrapper) $1);
        } catch (Throwable e) {
            throw new IllegalArgumentException(e);
        }
        if ($2.equals("address")) {
            w.address = (java.lang.String) $3;
            return;
        }
        throw new org.apache.dubbo.common.bytecode.NoSuchPropertyException("Not found property \"" + $2 + "\" field or setter method in class TestWrapper.");
    }
}
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