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/* * Copyright 2002-2006,2009 The Apache Software Foundation. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.opensymphony.xwork2.ognl.accessor; import com.opensymphony.xwork2.XWorkConstants; import com.opensymphony.xwork2.XWorkException; import com.opensymphony.xwork2.inject.Inject; import com.opensymphony.xwork2.ognl.OgnlValueStack; import com.opensymphony.xwork2.util.CompoundRoot; import com.opensymphony.xwork2.util.ValueStack; import com.opensymphony.xwork2.util.logging.Logger; import com.opensymphony.xwork2.util.logging.LoggerFactory; import ognl.*; import java.beans.IntrospectionException; import java.beans.PropertyDescriptor; import java.util.*; import static java.lang.String.format; import static org.apache.commons.lang3.BooleanUtils.toBoolean; /** * A stack that is able to call methods on objects in the stack. * * @author $Author$ * @author Rainer Hermanns * @version $Revision$ */ public class CompoundRootAccessor implements PropertyAccessor, MethodAccessor, ClassResolver { /** * Used by OGNl to generate bytecode */ public String getSourceAccessor(OgnlContext context, Object target, Object index) { return null; } /** * Used by OGNl to generate bytecode */ public String getSourceSetter(OgnlContext context, Object target, Object index) { return null; } private final static Logger LOG = LoggerFactory.getLogger(CompoundRootAccessor.class); private final static Class[] EMPTY_CLASS_ARRAY = new Class[0]; private static Map<MethodCall, Boolean> invalidMethods = new HashMap<MethodCall, Boolean>(); static boolean devMode = false; @Inject(XWorkConstants.DEV_MODE) public static void setDevMode(String mode) { devMode = "true".equals(mode); } public void setProperty(Map context, Object target, Object name, Object value) throws OgnlException { CompoundRoot root = (CompoundRoot) target; OgnlContext ognlContext = (OgnlContext) context; for (Object o : root) { if (o == null) { continue; } try { if (OgnlRuntime.hasSetProperty(ognlContext, o, name)) { OgnlRuntime.setProperty(ognlContext, o, name, value); return; } else if (o instanceof Map) { @SuppressWarnings("unchecked") Map<Object, Object> map = (Map<Object, Object>) o; try { map.put(name, value); return; } catch (UnsupportedOperationException e) { // This is an unmodifiable Map, so move on to the next element in the stack } } // } catch (OgnlException e) { // if (e.getReason() != null) { // final String msg = "Caught an Ognl exception while setting property " + name; // log.error(msg, e); // throw new RuntimeException(msg, e.getReason()); // } } catch (IntrospectionException e) { // this is OK if this happens, we'll just keep trying the next } } boolean reportError = toBoolean((Boolean) context.get(ValueStack.REPORT_ERRORS_ON_NO_PROP)); if (reportError || devMode) { final String msg = format("No object in the CompoundRoot has a publicly accessible property named '%s' " + "(no setter could be found).", name); if (reportError) { throw new XWorkException(msg); } else { LOG.warn(msg); } } } public Object getProperty(Map context, Object target, Object name) throws OgnlException { CompoundRoot root = (CompoundRoot) target; OgnlContext ognlContext = (OgnlContext) context; if (name instanceof Integer) { Integer index = (Integer) name; return root.cutStack(index); } else if (name instanceof String) { if ("top".equals(name)) { if (root.size() > 0) { return root.get(0); } else { return null; } } for (Object o : root) { if (o == null) { continue; } try { if ((OgnlRuntime.hasGetProperty(ognlContext, o, name)) || ((o instanceof Map) && ((Map) o).containsKey(name))) { return OgnlRuntime.getProperty(ognlContext, o, name); } } catch (OgnlException e) { if (e.getReason() != null) { final String msg = "Caught an Ognl exception while getting property " + name; throw new XWorkException(msg, e); } } catch (IntrospectionException e) { // this is OK if this happens, we'll just keep trying the next } } //property was not found if (context.containsKey(OgnlValueStack.THROW_EXCEPTION_ON_FAILURE)) throw new NoSuchPropertyException(target, name); else return null; } else { return null; } } public Object callMethod(Map context, Object target, String name, Object[] objects) throws MethodFailedException { CompoundRoot root = (CompoundRoot) target; if ("describe".equals(name)) { Object v; if (objects != null && objects.length == 1) { v = objects[0]; } else { v = root.get(0); } if (v instanceof Collection || v instanceof Map || v.getClass().isArray()) { return v.toString(); } try { Map<String, PropertyDescriptor> descriptors = OgnlRuntime.getPropertyDescriptors(v.getClass()); int maxSize = 0; for (String pdName : descriptors.keySet()) { if (pdName.length() > maxSize) { maxSize = pdName.length(); } } SortedSet<String> set = new TreeSet<String>(); StringBuffer sb = new StringBuffer(); for (PropertyDescriptor pd : descriptors.values()) { sb.append(pd.getName()).append(": "); int padding = maxSize - pd.getName().length(); for (int i = 0; i < padding; i++) { sb.append(" "); } sb.append(pd.getPropertyType().getName()); set.add(sb.toString()); sb = new StringBuffer(); } sb = new StringBuffer(); for (Object aSet : set) { String s = (String) aSet; sb.append(s).append("\n"); } return sb.toString(); } catch (IntrospectionException e) { if (LOG.isDebugEnabled()) { LOG.debug("Got exception in callMethod", e); } } catch (OgnlException e) { if (LOG.isDebugEnabled()) { LOG.debug("Got exception in callMethod", e); } } return null; } for (Object o : root) { if (o == null) { continue; } Class clazz = o.getClass(); Class[] argTypes = getArgTypes(objects); MethodCall mc = null; if (argTypes != null) { mc = new MethodCall(clazz, name, argTypes); } if ((argTypes == null) || !invalidMethods.containsKey(mc)) { try { Object value = OgnlRuntime.callMethod((OgnlContext) context, o, name, objects); if (value != null) { return value; } } catch (OgnlException e) { // try the next one Throwable reason = e.getReason(); if (!context.containsKey(OgnlValueStack.THROW_EXCEPTION_ON_FAILURE) && (mc != null) && (reason != null) && (reason.getClass() == NoSuchMethodException.class)) { invalidMethods.put(mc, Boolean.TRUE); } else if (reason != null) { throw new MethodFailedException(o, name, e.getReason()); } } } } return null; } public Object callStaticMethod(Map transientVars, Class aClass, String s, Object[] objects) throws MethodFailedException { return null; } public Class classForName(String className, Map context) throws ClassNotFoundException { Object root = Ognl.getRoot(context); try { if (root instanceof CompoundRoot) { if (className.startsWith("vs")) { CompoundRoot compoundRoot = (CompoundRoot) root; if ("vs".equals(className)) { return compoundRoot.peek().getClass(); } int index = Integer.parseInt(className.substring(2)); return compoundRoot.get(index - 1).getClass(); } } } catch (Exception e) { if (LOG.isDebugEnabled()) { LOG.debug("Got exception when tried to get class for name [#0]", e, className); } } return Thread.currentThread().getContextClassLoader().loadClass(className); } private Class[] getArgTypes(Object[] args) { if (args == null) { return EMPTY_CLASS_ARRAY; } Class[] classes = new Class[args.length]; for (int i = 0; i < args.length; i++) { Object arg = args[i]; classes[i] = (arg != null) ? arg.getClass() : Object.class; } return classes; } static class MethodCall { Class clazz; String name; Class[] args; int hash; public MethodCall(Class clazz, String name, Class[] args) { this.clazz = clazz; this.name = name; this.args = args; this.hash = clazz.hashCode() + name.hashCode(); for (Class arg : args) { hash += arg.hashCode(); } } @Override public boolean equals(Object obj) { MethodCall mc = (CompoundRootAccessor.MethodCall) obj; return (mc.clazz.equals(clazz) && mc.name.equals(name) && Arrays.equals(mc.args, args)); } @Override public int hashCode() { return hash; } } }