runtime/org.argeo.slc.core/src/main/java/org/argeo/slc/core/execution/ExecutionParameterPostProcessor.java

   1 /*
   2  * Copyright (C) 2010 Mathieu Baudier <mbaudier@argeo.org>
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package org.argeo.slc.core.execution;
  18
  19 import java.beans.PropertyDescriptor;
  20 import java.util.HashSet;
  21 import java.util.Iterator;
  22 import java.util.List;
  23 import java.util.Map;
  24 import java.util.Set;
  25
  26 import org.apache.commons.logging.Log;
  27 import org.apache.commons.logging.LogFactory;
  28 import org.argeo.slc.SlcException;
  29 import org.argeo.slc.execution.ExecutionContext;
  30 import org.argeo.slc.execution.ExecutionFlow;
  31 import org.springframework.beans.BeansException;
  32 import org.springframework.beans.MutablePropertyValues;
  33 import org.springframework.beans.PropertyValue;
  34 import org.springframework.beans.PropertyValues;
  35 import org.springframework.beans.factory.BeanDefinitionStoreException;
  36 import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;
  37 import org.springframework.beans.factory.config.TypedStringValue;
  38 import org.springframework.beans.factory.support.ManagedList;
  39 import org.springframework.beans.factory.support.ManagedMap;
  40 import org.springframework.beans.factory.support.ManagedSet;
  41 import org.springframework.util.ObjectUtils;
  42 import org.springframework.util.StringUtils;
  43
  44 public class ExecutionParameterPostProcessor extends
  45                 InstantiationAwareBeanPostProcessorAdapter {
  46
  47         private final static Log log = LogFactory
  48                         .getLog(ExecutionParameterPostProcessor.class);
  49
  50         private ExecutionContext executionContext;
  51         private InstantiationManager instantiationManager;
  52
  53         private String placeholderPrefix = "@{";
  54         private String placeholderSuffix = "}";
  55         private String nullValue;
  56
  57         @Override
  58         public PropertyValues postProcessPropertyValues(PropertyValues pvs,
  59                         PropertyDescriptor[] pds, Object bean, String beanName)
  60                         throws BeansException {
  61
  62                 // TODO: resolve at execution only if scope is execution
  63                 // TODO: deal with placeholders in RuntimeBeanReference and
  64                 // RuntimeBeanNameReference
  65
  66                 MutablePropertyValues newPvs = new MutablePropertyValues();
  67
  68                 boolean changesOccured = false;
  69
  70                 for (PropertyValue pv : pvs.getPropertyValues()) {
  71                         Object convertedValue = resolveValue(beanName, bean, pv.getValue());
  72                         newPvs.addPropertyValue(new PropertyValue(pv, convertedValue));
  73                         if (convertedValue != pv.getValue()) {
  74                                 changesOccured = true;
  75                         }
  76                 }
  77
  78                 return changesOccured ? newPvs : pvs;
  79         }
  80
  81         @Override
  82         public boolean postProcessAfterInstantiation(Object bean, String beanName)
  83                         throws BeansException {
  84                 if (bean instanceof ExecutionFlow)
  85                         instantiationManager.flowInitializationStarted(
  86                                         (ExecutionFlow) bean, beanName);
  87                 return true;
  88         }
  89
  90         @Override
  91         public Object postProcessAfterInitialization(Object bean, String beanName)
  92                         throws BeansException {
  93                 if (bean instanceof ExecutionFlow)
  94                         instantiationManager.flowInitializationFinished(
  95                                         (ExecutionFlow) bean, beanName);
  96                 return bean;
  97         }
  98
  99         protected String resolvePlaceholder(Object bean, String placeholder) {
 100                 if (instantiationManager.isInFlowInitialization())
 101                         return instantiationManager.getInitializingFlowParameter(
 102                                         placeholder).toString();
 103
 104                 else {// execution
 105                         // next call fail if no execution context available
 106                         Object obj = executionContext.getVariable(placeholder);
 107                         if (obj != null) {
 108                                 return obj.toString();
 109                         }
 110                 }
 111
 112                 return null;
 113         }
 114
 115         @SuppressWarnings(value = { "unchecked" })
 116         public Object resolveValue(String beanName, Object bean, Object value) {
 117                 if (value instanceof TypedStringValue) {
 118                         TypedStringValue tsv = (TypedStringValue) value;
 119                         String originalValue = tsv.getValue();
 120
 121                         String convertedValue = resolveString(beanName, bean, originalValue);
 122                         if (convertedValue == null)
 123                                 return null;
 124                         return convertedValue.equals(originalValue) ? value
 125                                         : new TypedStringValue(convertedValue);
 126                 } else if (value instanceof String) {
 127                         String originalValue = value.toString();
 128                         String convertedValue = resolveString(beanName, bean, originalValue);
 129                         if (convertedValue == null)
 130                                 return null;
 131                         return convertedValue.equals(originalValue) ? value
 132                                         : convertedValue;
 133                 } else if (value instanceof ManagedMap) {
 134                         Map mapVal = (Map) value;
 135
 136                         Map newContent = new ManagedMap();
 137                         boolean entriesModified = false;
 138                         for (Iterator it = mapVal.entrySet().iterator(); it.hasNext();) {
 139                                 Map.Entry entry = (Map.Entry) it.next();
 140                                 Object key = entry.getKey();
 141                                 int keyHash = (key != null ? key.hashCode() : 0);
 142                                 Object newKey = resolveValue(beanName, bean, key);
 143                                 int newKeyHash = (newKey != null ? newKey.hashCode() : 0);
 144                                 Object val = entry.getValue();
 145                                 Object newVal = resolveValue(beanName, bean, val);
 146                                 newContent.put(newKey, newVal);
 147                                 entriesModified = entriesModified
 148                                                 || (newVal != val || newKey != key || newKeyHash != keyHash);
 149                         }
 150
 151                         return entriesModified ? newContent : value;
 152                 } else if (value instanceof ManagedList) {
 153                         List listVal = (List) value;
 154                         List newContent = new ManagedList();
 155                         boolean valueModified = false;
 156
 157                         for (int i = 0; i < listVal.size(); i++) {
 158                                 Object elem = listVal.get(i);
 159                                 Object newVal = resolveValue(beanName, bean, elem);
 160                                 newContent.add(newVal);
 161                                 if (!ObjectUtils.nullSafeEquals(newVal, elem)) {
 162                                         valueModified = true;
 163                                 }
 164                         }
 165                         return valueModified ? newContent : value;
 166                 } else if (value instanceof ManagedSet) {
 167                         Set setVal = (Set) value;
 168                         Set newContent = new ManagedSet();
 169                         boolean entriesModified = false;
 170                         for (Iterator it = setVal.iterator(); it.hasNext();) {
 171                                 Object elem = it.next();
 172                                 int elemHash = (elem != null ? elem.hashCode() : 0);
 173                                 Object newVal = resolveValue(beanName, bean, elem);
 174                                 int newValHash = (newVal != null ? newVal.hashCode() : 0);
 175                                 newContent.add(newVal);
 176                                 entriesModified = entriesModified
 177                                                 || (newVal != elem || newValHash != elemHash);
 178                         }
 179                         return entriesModified ? newContent : value;
 180                 } else {
 181                         // log.debug(beanName + ": " + value.getClass() + " : " + value);
 182                         return value;
 183                 }
 184
 185         }
 186
 187         private String resolveString(String beanName, Object bean, String strVal) {
 188                 // in case <null/> is passed
 189                 if (strVal == null)
 190                         return null;
 191
 192                 String value = parseStringValue(bean, strVal, new HashSet<String>());
 193
 194                 if (value == null)
 195                         throw new SlcException("Could not resolve placeholder '" + strVal
 196                                         + "' in bean '" + beanName + "'");
 197
 198                 return (value.equals(nullValue) ? null : value);
 199         }
 200
 201         public void setPlaceholderPrefix(String placeholderPrefix) {
 202                 this.placeholderPrefix = placeholderPrefix;
 203         }
 204
 205         public void setPlaceholderSuffix(String placeholderSuffix) {
 206                 this.placeholderSuffix = placeholderSuffix;
 207         }
 208
 209         public void setNullValue(String nullValue) {
 210                 this.nullValue = nullValue;
 211         }
 212
 213         public void setInstantiationManager(
 214                         InstantiationManager instantiationManager) {
 215                 this.instantiationManager = instantiationManager;
 216         }
 217
 218         public void setExecutionContext(ExecutionContext executionContext) {
 219                 this.executionContext = executionContext;
 220         }
 221
 222         //
 223         // Following methods hacked from the internals of
 224         // PropertyPlaceholderConfigurer
 225         //
 226
 227         protected String parseStringValue(Object bean, String strVal,
 228                         Set<String> visitedPlaceholders)
 229                         throws BeanDefinitionStoreException {
 230
 231                 // in case <null/> is passed
 232                 if (strVal == null)
 233                         return null;
 234
 235                 StringBuffer buf = new StringBuffer(strVal);
 236
 237                 int startIndex = strVal.indexOf(placeholderPrefix);
 238                 while (startIndex != -1) {
 239                         int endIndex = findPlaceholderEndIndex(buf, startIndex);
 240                         if (endIndex != -1) {
 241                                 String placeholder = buf.substring(startIndex
 242                                                 + placeholderPrefix.length(), endIndex);
 243                                 if (!visitedPlaceholders.add(placeholder)) {
 244                                         throw new BeanDefinitionStoreException(
 245                                                         "Circular placeholder reference '" + placeholder
 246                                                                         + "' in property definitions");
 247                                 }
 248                                 // Recursive invocation, parsing placeholders contained in
 249                                 // the placeholder key.
 250                                 placeholder = parseStringValue(bean, placeholder,
 251                                                 visitedPlaceholders);
 252                                 // Now obtain the value for the fully resolved key...
 253                                 String propVal = resolvePlaceholder(bean, placeholder);
 254                                 if (propVal != null) {
 255                                         // Recursive invocation, parsing placeholders contained
 256                                         // in the
 257                                         // previously resolved placeholder value.
 258                                         propVal = parseStringValue(bean, propVal,
 259                                                         visitedPlaceholders);
 260                                         buf.replace(startIndex, endIndex
 261                                                         + placeholderSuffix.length(), propVal);
 262                                         if (log.isTraceEnabled()) {
 263                                                 log.trace("Resolved placeholder '" + placeholder + "'");
 264                                         }
 265                                         startIndex = buf.indexOf(placeholderPrefix, startIndex
 266                                                         + propVal.length());
 267                                 } else {
 268                                         throw new BeanDefinitionStoreException(
 269                                                         "Could not resolve placeholder '" + placeholder
 270                                                                         + "'");
 271                                 }
 272                                 visitedPlaceholders.remove(placeholder);
 273                         } else {
 274                                 startIndex = -1;
 275                         }
 276                 }
 277
 278                 return buf.toString();
 279         }
 280
 281         private int findPlaceholderEndIndex(CharSequence buf, int startIndex) {
 282                 int index = startIndex + placeholderPrefix.length();
 283                 int withinNestedPlaceholder = 0;
 284                 while (index < buf.length()) {
 285                         if (StringUtils.substringMatch(buf, index, placeholderSuffix)) {
 286                                 if (withinNestedPlaceholder > 0) {
 287                                         withinNestedPlaceholder--;
 288                                         index = index + placeholderSuffix.length();
 289                                 } else {
 290                                         return index;
 291                                 }
 292                         } else if (StringUtils
 293                                         .substringMatch(buf, index, placeholderPrefix)) {
 294                                 withinNestedPlaceholder++;
 295                                 index = index + placeholderPrefix.length();
 296                         } else {
 297                                 index++;
 298                         }
 299                 }
 300                 return -1;
 301         }
 302
 303 }