CompoundRoot root;
transient Map<String, Object> context;
Class defaultType;
Map<Object, Object> overrides;
transient OgnlUtil ognlUtil;
transient SecurityMemberAccess securityMemberAccess;
protected OgnlValueStack(XWorkConverter xworkConverter, CompoundRootAccessor accessor, TextProvider prov, boolean allowStaticAccess) {
setRoot(xworkConverter, accessor, new CompoundRoot(), allowStaticAccess);
push(prov);
}
protected OgnlValueStack(ValueStack vs, XWorkConverter xworkConverter, CompoundRootAccessor accessor, boolean allowStaticAccess) {
setRoot(xworkConverter, accessor, new CompoundRoot(vs.getRoot()), allowStaticAccess);
}
//注入OgnlUtil对象
@Inject
public void setOgnlUtil(OgnlUtil ognlUtil) {
this.ognlUtil = ognlUtil;
}
protected void setRoot(XWorkConverter xworkConverter,
CompoundRootAccessor accessor, CompoundRoot compoundRoot, boolean allowStaticMethodAccess) {
this.root = compoundRoot;
this.securityMemberAccess = new SecurityMemberAccess(allowStaticMethodAccess);
this.context = Ognl.createDefaultContext(this.root, accessor, new OgnlTypeConverterWrapper(xworkConverter),
securityMemberAccess);
context.put(VALUE_STACK, this);
Ognl.setClassResolver(context, accessor);
((OgnlContext) context).setTraceEvaluations(false);
((OgnlContext) context).setKeepLastEvaluation(false);
}
@Inject("devMode")
public void setDevMode(String mode) {
devMode = "true".equalsIgnoreCase(mode);
}
@Inject(value = "logMissingProperties", required = false )
public void setLogMissingProperties(String logMissingProperties) {
this.logMissingProperties = "true".equalsIgnoreCase(logMissingProperties);
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#getContext()
*/
public Map<String, Object> getContext() {
return context;
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#setDefaultType(java.lang.Class)
*/
public void setDefaultType(Class defaultType) {
this.defaultType = defaultType;
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#setExprOverrides(java.util.Map)
*/
public void setExprOverrides(Map<Object, Object> overrides) {
if (this.overrides == null) {
this.overrides = overrides;
} else {
this.overrides.putAll(overrides);
}
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#getExprOverrides()
*/
public Map<Object, Object> getExprOverrides() {
return this.overrides;
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#getRoot()
*/
public CompoundRoot getRoot() {
return root;
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#setValue(java.lang.String, java.lang.Object)
*/
public void setValue(String expr, Object value) {
setValue(expr, value, devMode);
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#setValue(java.lang.String, java.lang.Object, boolean)
*/
public void setValue(String expr, Object value, boolean throwExceptionOnFailure) {
Map<String, Object> context = getContext();
try {
context.put(XWorkConverter.CONVERSION_PROPERTY_FULLNAME, expr);
context.put(REPORT_ERRORS_ON_NO_PROP, (throwExceptionOnFailure) ? Boolean.TRUE : Boolean.FALSE);
ognlUtil.setValue(expr, context, root, value);
} catch (OgnlException e) {
String msg = "Error setting expression '" + expr + "' with value '" + value + "'";
if (LOG.isWarnEnabled()) {
LOG.warn(msg, e);
}
if (throwExceptionOnFailure) {
throw new XWorkException(msg, e);
}
} catch (RuntimeException re) { //XW-281
if (throwExceptionOnFailure) {
StringBuilder msg = new StringBuilder();
msg.append("Error setting expression '");
msg.append(expr);
msg.append("' with value ");
//值栈中数组的处理方式
if (value instanceof Object[]) {
Object[] valueArray = (Object[]) value;
msg.append("[");
for (int index = 0; index < valueArray.length; index++) {
msg.append("'");
msg.append(valueArray[index]);
msg.append("'");
if (index < (valueArray.length + 1))
msg.append(", ");
}
msg.append("]");
} else {
msg.append("'");
msg.append(value);
msg.append("'");
}
throw new XWorkException(msg.toString(), re);
} else {
if (LOG.isWarnEnabled()) {
LOG.warn("Error setting value", re);
}
}
} finally {
ReflectionContextState.clear(context);
context.remove(XWorkConverter.CONVERSION_PROPERTY_FULLNAME);
context.remove(REPORT_ERRORS_ON_NO_PROP);
}
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#findString(java.lang.String)
*/
public String findString(String expr) {
return (String) findValue(expr, String.class);
}
public String findString(String expr, boolean throwExceptionOnFailure) {
return (String) findValue(expr, String.class, throwExceptionOnFailure);
}
/* 从值栈中获取对象的值
* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#findValue(java.lang.String)
*/
public Object findValue(String expr, boolean throwExceptionOnFailure) {
try {
if (expr == null) {
return null;
}
if ((overrides != null) && overrides.containsKey(expr)) {
expr = (String) overrides.get(expr);
}
if (defaultType != null) {
return findValue(expr, defaultType);
}
Object value = ognlUtil.getValue(expr, context, root);
if (value != null) {
return value;
} else {
checkForInvalidProperties(expr, throwExceptionOnFailure, throwExceptionOnFailure);
return findInContext(expr);
}
} catch (OgnlException e) {
checkForInvalidProperties(expr, throwExceptionOnFailure, throwExceptionOnFailure);
return findInContext(expr);
} catch (Exception e) {
logLookupFailure(expr, e);
if (throwExceptionOnFailure)
throw new XWorkException(e);
return findInContext(expr);
} finally {
ReflectionContextState.clear(context);
}
}
public Object findValue(String expr) {
return findValue(expr, false);
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#findValue(java.lang.String, java.lang.Class)
*/
public Object findValue(String expr, Class asType, boolean throwExceptionOnFailure) {
try {
if (expr == null) {
return null;
}
if ((overrides != null) && overrides.containsKey(expr)) {
expr = (String) overrides.get(expr);
}
Object value = ognlUtil.getValue(expr, context, root, asType);
if (value != null) {
return value;
} else {
checkForInvalidProperties(expr, throwExceptionOnFailure, throwExceptionOnFailure);
return findInContext(expr);
}
} catch (OgnlException e) {
checkForInvalidProperties(expr, throwExceptionOnFailure, throwExceptionOnFailure);
return findInContext(expr);
} catch (Exception e) {
logLookupFailure(expr, e);
if (throwExceptionOnFailure)
throw new XWorkException(e);
return findInContext(expr);
} finally {
ReflectionContextState.clear(context);
}
}
private Object findInContext(String name) {
return getContext().get(name);
}
public Object findValue(String expr, Class asType) {
return findValue(expr, asType, false);
}
/**
* This method looks for matching methods/properties in an action to warn the user if
* they specified a property that doesn't exist.
*
* @param expr the property expression
*/
private void checkForInvalidProperties(String expr, boolean throwExceptionPropNotFound, boolean throwExceptionMethodFound) {
if (expr.contains("(") && expr.contains(")")) {
if (devMode)
LOG.warn("Could not find method [" + expr + "]");
if (throwExceptionMethodFound)
throw new XWorkException("Could not find method [" + expr + "]");
} else if (findInContext(expr) == null) {
// find objects with Action in them and inspect matching getters
Set<String> availableProperties = new LinkedHashSet<String>();
for (Object o : root) {
if (o instanceof ActionSupport || o.getClass().getSimpleName().endsWith("Action")) {
try {
findAvailableProperties(o.getClass(), expr, availableProperties, null);
} catch (IntrospectionException ise) {
// ignore
}
}
}
if (!availableProperties.contains(expr)) {
if (devMode && logMissingProperties) {
LOG.warn("Could not find property [" + expr + "]");
}
if (throwExceptionMethodFound)
throw new XWorkException("Could not find property [" + expr + "]");
}
}
}
/**
* Look for available properties on an existing class.
*
* @param c the class to search on
* @param expr the property expression
* @param availableProperties a set of properties found
* @param parent a parent property
* @throws IntrospectionException when Ognl can't get property descriptors
*/
private void findAvailableProperties(Class c, String expr, Set<String> availableProperties, String parent) throws IntrospectionException {
PropertyDescriptor[] descriptors = ognlUtil.getPropertyDescriptors(c);
for (PropertyDescriptor pd : descriptors) {
String name = pd.getDisplayName();
if (parent != null && expr.contains(".")) {
name = expr.substring(0, expr.indexOf(".") + 1) + name;
}
if (expr.startsWith(name)) {
availableProperties.add((parent != null) ? parent + "." + name : name);
if (expr.equals(name)) break; // no need to go any further
if (expr.contains(".")) {
String property = expr.substring(expr.indexOf(".") + 1);
// if there is a nested property (indicated by a dot), chop it off so we can look for method name
String rawProperty = (property.contains(".")) ? property.substring(0, property.indexOf(".")) : property;
String methodToLookFor = "get" + rawProperty.substring(0, 1).toUpperCase() + rawProperty.substring(1);
Method[] methods = pd.getPropertyType().getDeclaredMethods();
for (Method method : methods) {
if (method.getName().equals(methodToLookFor)) {
availableProperties.add(name + "." + rawProperty);
Class returnType = method.getReturnType();
findAvailableProperties(returnType, property, availableProperties, name);
}
}
}
}
}
}
/**
* Log a failed lookup, being more verbose when devMode=true.
*
* @param expr The failed expression
* @param e The thrown exception.
*/
private void logLookupFailure(String expr, Exception e) {
String msg = LoggerUtils.format("Caught an exception while evaluating expression '#0' against value stack", expr);
if (devMode && LOG.isWarnEnabled()) {
LOG.warn(msg, e);
LOG.warn("NOTE: Previous warning message was issued due to devMode set to true.");
} else if (LOG.isDebugEnabled()) {
LOG.debug(msg, e);
}
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#peek()
*/
public Object peek() {
return root.peek();
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#pop()
*/
public Object pop() {
return root.pop();
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#push(java.lang.Object)
*/
public void push(Object o) {
root.push(o);
}
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#set(java.lang.String, java.lang.Object)
*/
public void set(String key, Object o) {
//set basically is backed by a Map
//pushed on the stack with a key
//being put on the map and the
//Object being the value
Map setMap = null;
//check if this is a Map
//put on the stack for setting
//if so just use the old map (reduces waste)
Object topObj = peek();
if (topObj instanceof Map
&& ((Map) topObj).get(MAP_IDENTIFIER_KEY) != null) {
setMap = (Map) topObj;
} else {
setMap = new HashMap();
//the map identifier key ensures
//that this map was put there
//for set purposes and not by a user
//whose data we don't want to touch
setMap.put(MAP_IDENTIFIER_KEY, "");
push(setMap);
}
setMap.put(key, o);
}
private static final String MAP_IDENTIFIER_KEY = "com.opensymphony.xwork2.util.OgnlValueStack.MAP_IDENTIFIER_KEY";
/* (non-Javadoc)
* @see com.opensymphony.xwork2.util.ValueStack#size()
*/
public int size() {
return root.size();
}
private Object readResolve() {
// TODO: this should be done better
ActionContext ac = ActionContext.getContext();
Container cont = ac.getContainer();
XWorkConverter xworkConverter = cont.getInstance(XWorkConverter.class);
CompoundRootAccessor accessor = (CompoundRootAccessor) cont.getInstance(PropertyAccessor.class, CompoundRoot.class.getName());
TextProvider prov = cont.getInstance(TextProvider.class, "system");
boolean allow = "true".equals(cont.getInstance(String.class, "allowStaticMethodAccess"));
OgnlValueStack aStack = new OgnlValueStack(xworkConverter, accessor, prov, allow);
aStack.setOgnlUtil(cont.getInstance(OgnlUtil.class));
aStack.setRoot(xworkConverter, accessor, this.root, allow);
return aStack;
}
public void clearContextValues() {
//this is an OGNL ValueStack so the context will be an OgnlContext
//it would be better to make context of type OgnlContext
((OgnlContext)context).getValues().clear();
}
public void setAcceptProperties(Set<Pattern> acceptedProperties) {
securityMemberAccess.setAcceptProperties(acceptedProperties);
}
public void setExcludeProperties(Set<Pattern> excludeProperties) {
securityMemberAccess.setExcludeProperties(excludeProperties);
}
}
