OgnlValueStack.java
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.struts2.ognl;
import org.apache.struts2.ActionContext;
import org.apache.struts2.text.TextProvider;
import org.apache.struts2.conversion.impl.XWorkConverter;
import org.apache.struts2.inject.Container;
import org.apache.struts2.inject.Inject;
import org.apache.struts2.ognl.accessor.RootAccessor;
import org.apache.struts2.util.ClearableValueStack;
import org.apache.struts2.util.CompoundRoot;
import org.apache.struts2.util.MemberAccessValueStack;
import org.apache.struts2.util.ValueStack;
import org.apache.struts2.util.reflection.ReflectionContextState;
import ognl.MethodFailedException;
import ognl.NoSuchPropertyException;
import ognl.Ognl;
import ognl.OgnlContext;
import ognl.OgnlException;
import org.apache.commons.lang3.BooleanUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.struts2.StrutsConstants;
import org.apache.struts2.StrutsException;
import java.io.Serial;
import java.io.Serializable;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.regex.Pattern;
/**
* Ognl implementation of a value stack that allows for dynamic Ognl expressions to be evaluated against it. When evaluating an expression,
* the stack will be searched down the stack, from the latest objects pushed in to the earliest, looking for a bean with a getter or setter
* for the given property or a method of the given name (depending on the expression being evaluated).
*
* @author Patrick Lightbody
* @author tm_jee
* @version $Date$ $Id$
*/
public class OgnlValueStack implements Serializable, ValueStack, ClearableValueStack, MemberAccessValueStack {
public static final String THROW_EXCEPTION_ON_FAILURE = OgnlValueStack.class.getName() + ".throwExceptionOnFailure";
private static final Logger LOG = LogManager.getLogger(OgnlValueStack.class);
@Serial
private static final long serialVersionUID = 370737852934925530L;
private static final String MAP_IDENTIFIER_KEY = "org.apache.struts2.util.OgnlValueStack.MAP_IDENTIFIER_KEY";
protected CompoundRoot root;
protected transient Map<String, Object> context;
protected Class defaultType;
protected Map<Object, Object> overrides;
protected transient OgnlUtil ognlUtil;
protected transient SecurityMemberAccess securityMemberAccess;
private transient XWorkConverter converter;
private boolean devMode;
private boolean logMissingProperties;
private boolean shouldFallbackToContext = true;
/**
* @since 6.4.0
*/
protected OgnlValueStack(ValueStack vs,
XWorkConverter xworkConverter,
RootAccessor accessor,
TextProvider prov,
SecurityMemberAccess securityMemberAccess) {
setRoot(xworkConverter,
accessor,
vs != null ? new CompoundRoot(vs.getRoot()) : new CompoundRoot(),
securityMemberAccess);
if (prov != null) {
push(prov);
}
}
/**
* @since 6.4.0
*/
protected OgnlValueStack(XWorkConverter xworkConverter, RootAccessor accessor, TextProvider prov, SecurityMemberAccess securityMemberAccess) {
this(null, xworkConverter, accessor, prov, securityMemberAccess);
}
/**
* @since 6.4.0
*/
protected OgnlValueStack(ValueStack vs, XWorkConverter xworkConverter, RootAccessor accessor, SecurityMemberAccess securityMemberAccess) {
this(vs, xworkConverter, accessor, null, securityMemberAccess);
}
@Inject
protected void setOgnlUtil(OgnlUtil ognlUtil) {
this.ognlUtil = ognlUtil;
}
/**
* @since 6.4.0
*/
protected void setRoot(XWorkConverter xworkConverter, RootAccessor accessor, CompoundRoot compoundRoot, SecurityMemberAccess securityMemberAccess) {
this.root = compoundRoot;
this.securityMemberAccess = securityMemberAccess;
this.context = Ognl.createDefaultContext(this.root, securityMemberAccess, accessor, new OgnlTypeConverterWrapper(xworkConverter));
this.converter = xworkConverter;
context.put(VALUE_STACK, this);
((OgnlContext) context).setTraceEvaluations(false);
((OgnlContext) context).setKeepLastEvaluation(false);
}
@Inject(StrutsConstants.STRUTS_DEVMODE)
protected void setDevMode(String mode) {
this.devMode = BooleanUtils.toBoolean(mode);
}
@Inject(value = StrutsConstants.STRUTS_OGNL_LOG_MISSING_PROPERTIES, required = false)
protected void setLogMissingProperties(String logMissingProperties) {
this.logMissingProperties = BooleanUtils.toBoolean(logMissingProperties);
}
@Inject(value = StrutsConstants.STRUTS_OGNL_VALUE_STACK_FALLBACK_TO_CONTEXT, required = false)
protected void setShouldFallbackToContext(String shouldFallbackToContext) {
this.shouldFallbackToContext = BooleanUtils.toBoolean(shouldFallbackToContext);
}
/**
* @see org.apache.struts2.util.ValueStack#getContext()
*/
@Override
public Map<String, Object> getContext() {
return context;
}
@Override
public ActionContext getActionContext() {
return ActionContext.of(context);
}
/**
* @see org.apache.struts2.util.ValueStack#setDefaultType(java.lang.Class)
*/
@Override
public void setDefaultType(Class defaultType) {
this.defaultType = defaultType;
}
/**
* @see org.apache.struts2.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);
}
}
/**
* @see org.apache.struts2.util.ValueStack#getExprOverrides()
*/
@Override
public Map<Object, Object> getExprOverrides() {
return this.overrides;
}
/**
* @see org.apache.struts2.util.ValueStack#getRoot()
*/
@Override
public CompoundRoot getRoot() {
return root;
}
/**
* @see org.apache.struts2.util.ValueStack#setParameter(String, Object)
*/
@Override
public void setParameter(String expr, Object value) {
setValue(expr, value, devMode);
}
/**
* @see org.apache.struts2.util.ValueStack#setValue(java.lang.String, java.lang.Object)
*/
@Override
public void setValue(String expr, Object value) {
setValue(expr, value, devMode);
}
/**
* @see org.apache.struts2.util.ValueStack#setValue(java.lang.String, java.lang.Object, boolean)
*/
@Override
public void setValue(String expr, Object value, boolean throwExceptionOnFailure) {
Map<String, Object> context = getContext();
try {
trySetValue(expr, value, throwExceptionOnFailure, context);
} catch (OgnlException e) {
handleOgnlException(expr, value, throwExceptionOnFailure, e);
} catch (RuntimeException re) { //XW-281
handleRuntimeException(expr, value, throwExceptionOnFailure, re);
} finally {
cleanUpContext(context);
}
}
private void trySetValue(String expr, Object value, boolean throwExceptionOnFailure, Map<String, Object> context) throws OgnlException {
context.put(XWorkConverter.CONVERSION_PROPERTY_FULLNAME, expr);
context.put(REPORT_ERRORS_ON_NO_PROP, throwExceptionOnFailure || logMissingProperties ? Boolean.TRUE : Boolean.FALSE);
ognlUtil.setValue(expr, context, root, value);
}
private void cleanUpContext(Map<String, Object> context) {
ReflectionContextState.clear(context);
context.remove(XWorkConverter.CONVERSION_PROPERTY_FULLNAME);
context.remove(REPORT_ERRORS_ON_NO_PROP);
}
protected void handleRuntimeException(String expr, Object value, boolean throwExceptionOnFailure, RuntimeException re) {
if (throwExceptionOnFailure) {
String message = ErrorMessageBuilder.create()
.errorSettingExpressionWithValue(expr, value)
.build();
throw new StrutsException(message, re);
} else {
LOG.warn("Error setting value [{}] with expression [{}]", value, expr, re);
}
}
protected void handleOgnlException(String expr, Object value, boolean throwExceptionOnFailure, OgnlException e) {
if (e != null && e.getReason() instanceof SecurityException) {
LOG.error("Could not evaluate this expression due to security constraints: [{}]", expr, e);
}
boolean shouldLog = shouldLogMissingPropertyWarning(e);
String msg = null;
if (throwExceptionOnFailure || shouldLog) {
msg = ErrorMessageBuilder.create().errorSettingExpressionWithValue(expr, value).build();
}
if (shouldLog) {
LOG.warn(msg, e);
}
if (throwExceptionOnFailure) {
throw new StrutsException(msg, e);
}
}
/**
* @see org.apache.struts2.util.ValueStack#findString(java.lang.String)
*/
@Override
public String findString(String expr) {
return (String) findValue(expr, String.class);
}
@Override
public String findString(String expr, boolean throwExceptionOnFailure) {
return (String) findValue(expr, String.class, throwExceptionOnFailure);
}
/**
* @see org.apache.struts2.util.ValueStack#findValue(java.lang.String)
*/
@Override
public Object findValue(String expr, boolean throwExceptionOnFailure) {
try {
setupExceptionOnFailure(throwExceptionOnFailure);
return tryFindValueWhenExpressionIsNotNull(expr);
} catch (OgnlException e) {
return handleOgnlException(expr, throwExceptionOnFailure, e);
} catch (Exception e) {
return handleOtherException(expr, throwExceptionOnFailure, e);
} finally {
ReflectionContextState.clear(context);
}
}
protected void setupExceptionOnFailure(boolean throwExceptionOnFailure) {
if (throwExceptionOnFailure || logMissingProperties) {
context.put(THROW_EXCEPTION_ON_FAILURE, true);
}
}
private Object tryFindValueWhenExpressionIsNotNull(String expr) throws OgnlException {
if (expr == null) {
return null;
}
return tryFindValue(expr);
}
protected Object handleOtherException(String expr, boolean throwExceptionOnFailure, Exception e) {
logLookupFailure(expr, e);
if (throwExceptionOnFailure)
throw new StrutsException(e);
return findInContext(expr);
}
private Object tryFindValue(String expr) throws OgnlException {
return tryFindValue(expr, defaultType);
}
private String lookupForOverrides(String expr) {
if (overrides != null && overrides.containsKey(expr)) {
expr = (String) overrides.get(expr);
}
return expr;
}
@Override
public Object findValue(String expr) {
return findValue(expr, false);
}
/**
* @see org.apache.struts2.util.ValueStack#findValue(java.lang.String, java.lang.Class)
*/
@Override
public Object findValue(String expr, Class asType, boolean throwExceptionOnFailure) {
try {
setupExceptionOnFailure(throwExceptionOnFailure);
return tryFindValueWhenExpressionIsNotNull(expr, asType);
} catch (OgnlException e) {
final Object value = handleOgnlException(expr, throwExceptionOnFailure, e);
return converter.convertValue(getContext(), value, asType);
} catch (Exception e) {
final Object value = handleOtherException(expr, throwExceptionOnFailure, e);
return converter.convertValue(getContext(), value, asType);
} finally {
ReflectionContextState.clear(context);
}
}
private Object tryFindValueWhenExpressionIsNotNull(String expr, Class asType) throws OgnlException {
if (expr == null) {
return null;
}
return tryFindValue(expr, asType);
}
protected Object handleOgnlException(String expr, boolean throwExceptionOnFailure, OgnlException e) {
Object ret = null;
if (e != null && e.getReason() instanceof SecurityException) {
LOG.error("Could not evaluate this expression due to security constraints: [{}]", expr, e);
} else {
ret = findInContext(expr);
}
if (ret == null) {
if (shouldLogMissingPropertyWarning(e)) {
LOG.warn("Could not find property [{}]!", expr, e);
}
if (throwExceptionOnFailure) {
throw new StrutsException(e);
}
}
return ret;
}
protected boolean shouldLogMissingPropertyWarning(OgnlException e) {
return (e instanceof NoSuchPropertyException ||
(e instanceof MethodFailedException && e.getReason() instanceof NoSuchMethodException))
&& logMissingProperties;
}
private Object tryFindValue(String expr, Class asType) throws OgnlException {
try {
expr = lookupForOverrides(expr);
Object value = ognlUtil.getValue(expr, context, root, asType);
if (value == null) {
value = findInContext(expr);
if (value != null && asType != null) {
value = converter.convertValue(getContext(), value, asType);
}
}
return value;
} finally {
context.remove(THROW_EXCEPTION_ON_FAILURE);
}
}
protected Object findInContext(String name) {
if (!shouldFallbackToContext) {
return null;
}
return getContext().get(name);
}
@Override
public Object findValue(String expr, Class asType) {
return findValue(expr, asType, false);
}
/**
* 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) {
if (devMode) {
LOG.warn("Caught an exception while evaluating expression '{}' against value stack", expr, e);
LOG.warn("NOTE: Previous warning message was issued due to devMode set to true.");
} else {
LOG.debug("Caught an exception while evaluating expression '{}' against value stack", expr, e);
}
}
/**
* @see org.apache.struts2.util.ValueStack#peek()
*/
@Override
public Object peek() {
return root.peek();
}
/**
* @see org.apache.struts2.util.ValueStack#pop()
*/
@Override
public Object pop() {
return root.pop();
}
/**
* @see org.apache.struts2.util.ValueStack#push(java.lang.Object)
*/
@Override
public void push(Object o) {
root.push(o);
}
/**
* @see org.apache.struts2.util.ValueStack#set(java.lang.String, java.lang.Object)
*/
@Override
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 = retrieveSetMap();
setMap.put(key, o);
}
private Map retrieveSetMap() {
Map setMap;
Object topObj = peek();
if (shouldUseOldMap(topObj)) {
setMap = (Map) topObj;
} else {
setMap = new HashMap();
setMap.put(MAP_IDENTIFIER_KEY, "");
push(setMap);
}
return setMap;
}
/**
* check if this is a Map put on the stack for setting if so just use the old map (reduces waste)
*/
private boolean shouldUseOldMap(Object topObj) {
return topObj instanceof Map && ((Map) topObj).get(MAP_IDENTIFIER_KEY) != null;
}
/**
* @see org.apache.struts2.util.ValueStack#size()
*/
@Override
public int size() {
return root.size();
}
/**
* Retained for serializability - see {@link org.apache.struts2.ognl.OgnlValueStackTest#testSerializable}
*/
private Object readResolve() {
// TODO: this should be done better
ActionContext ac = ActionContext.getContext();
Container cont = ac.getContainer();
XWorkConverter xworkConverter = cont.getInstance(XWorkConverter.class);
RootAccessor accessor = cont.getInstance(RootAccessor.class);
TextProvider prov = cont.getInstance(TextProvider.class, "system");
SecurityMemberAccess sma = cont.getInstance(SecurityMemberAccess.class);
OgnlValueStack aStack = new OgnlValueStack(xworkConverter, accessor, prov, sma);
aStack.setOgnlUtil(cont.getInstance(OgnlUtil.class));
aStack.setRoot(xworkConverter, accessor, this.root, sma);
return aStack;
}
@Override
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();
}
@Override
public void useAcceptProperties(Set<Pattern> acceptedProperties) {
securityMemberAccess.useAcceptProperties(acceptedProperties);
}
@Override
public void useExcludeProperties(Set<Pattern> excludeProperties) {
securityMemberAccess.useExcludeProperties(excludeProperties);
}
}