org.yaml.snakeyaml.introspector.PropertyUtils Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of snakeyaml Show documentation
Show all versions of snakeyaml Show documentation
YAML 1.1 parser and emitter for Java
/**
* Copyright (c) 2008, http://www.snakeyaml.org
*
* 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 org.yaml.snakeyaml.introspector;
import java.beans.FeatureDescriptor;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import java.util.logging.Logger;
import org.yaml.snakeyaml.error.YAMLException;
import org.yaml.snakeyaml.util.PlatformFeatureDetector;
public class PropertyUtils {
final private static Logger log = Logger.getLogger(PropertyUtils.class.getPackage().getName());
private final Map, Map> propertiesCache = new HashMap, Map>();
private final Map, Set> readableProperties = new HashMap, Set>();
private BeanAccess beanAccess = BeanAccess.DEFAULT;
private boolean allowReadOnlyProperties = false;
private boolean skipMissingProperties = false;
private PlatformFeatureDetector platformFeatureDetector;
public PropertyUtils() {
this(new PlatformFeatureDetector());
}
PropertyUtils(PlatformFeatureDetector platformFeatureDetector) {
this.platformFeatureDetector = platformFeatureDetector;
/*
* Android lacks much of java.beans (including the Introspector class, used here), because java.beans classes tend to rely on java.awt, which isn't
* supported in the Android SDK. That means we have to fall back on FIELD access only when SnakeYAML is running on the Android Runtime.
*/
if (platformFeatureDetector.isRunningOnAndroid()) {
beanAccess = BeanAccess.FIELD;
}
}
protected Map getPropertiesMap(Class type, BeanAccess bAccess) {
if (propertiesCache.containsKey(type)) {
return propertiesCache.get(type);
}
Map properties = new LinkedHashMap();
boolean inaccessableFieldsExist = false;
switch (bAccess) {
case FIELD:
for (Class c = type; c != null; c = c.getSuperclass()) {
for (Field field : c.getDeclaredFields()) {
int modifiers = field.getModifiers();
if (!Modifier.isStatic(modifiers) && !Modifier.isTransient(modifiers)
&& !properties.containsKey(field.getName())) {
properties.put(field.getName(), new FieldProperty(field));
}
}
}
break;
default:
// add JavaBean properties
try {
for (PropertyDescriptor property : Introspector.getBeanInfo(type)
.getPropertyDescriptors()) {
Method readMethod = property.getReadMethod();
if ((readMethod == null || !readMethod.getName().equals("getClass"))
&& !isTransient(property)) {
properties.put(property.getName(), new MethodProperty(property));
}
}
} catch (IntrospectionException e) {
throw new YAMLException(e);
}
// add public fields
for (Class c = type; c != null; c = c.getSuperclass()) {
for (Field field : c.getDeclaredFields()) {
int modifiers = field.getModifiers();
if (!Modifier.isStatic(modifiers) && !Modifier.isTransient(modifiers)) {
if (Modifier.isPublic(modifiers)) {
properties.put(field.getName(), new FieldProperty(field));
} else {
inaccessableFieldsExist = true;
}
}
}
}
break;
}
if (properties.isEmpty() && inaccessableFieldsExist) {
throw new YAMLException("No JavaBean properties found in " + type.getName());
}
propertiesCache.put(type, properties);
return properties;
}
private boolean transientMethodChecked;
private Method isTransientMethod;
private boolean isTransient(FeatureDescriptor fd) {
if (!transientMethodChecked) {
transientMethodChecked = true;
try {
isTransientMethod = FeatureDescriptor.class.getDeclaredMethod("isTransient");
isTransientMethod.setAccessible(true);
} catch (NoSuchMethodException e) {
log.fine("NoSuchMethod: FeatureDescriptor.isTransient(). Don't check it anymore.");
} catch (SecurityException e) {
e.printStackTrace();
isTransientMethod = null;
}
}
if (isTransientMethod != null) {
try {
return Boolean.TRUE.equals(isTransientMethod.invoke(fd));
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (IllegalArgumentException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
isTransientMethod = null;
}
return false;
}
public Set getProperties(Class type) {
return getProperties(type, beanAccess);
}
public Set getProperties(Class type, BeanAccess bAccess) {
if (readableProperties.containsKey(type)) {
return readableProperties.get(type);
}
Set properties = createPropertySet(type, bAccess);
readableProperties.put(type, properties);
return properties;
}
protected Set createPropertySet(Class type, BeanAccess bAccess) {
Set properties = new TreeSet();
Collection props = getPropertiesMap(type, bAccess).values();
for (Property property : props) {
if (property.isReadable() && (allowReadOnlyProperties || property.isWritable())) {
properties.add(property);
}
}
return properties;
}
public Property getProperty(Class type, String name) {
return getProperty(type, name, beanAccess);
}
public Property getProperty(Class type, String name, BeanAccess bAccess) {
Map properties = getPropertiesMap(type, bAccess);
Property property = properties.get(name);
if (property == null && skipMissingProperties) {
property = new MissingProperty(name);
}
if (property == null) {
throw new YAMLException(
"Unable to find property '" + name + "' on class: " + type.getName());
}
return property;
}
public void setBeanAccess(BeanAccess beanAccess) {
if (platformFeatureDetector.isRunningOnAndroid() && beanAccess != BeanAccess.FIELD) {
throw new IllegalArgumentException("JVM is Android - only BeanAccess.FIELD is available");
}
if (this.beanAccess != beanAccess) {
this.beanAccess = beanAccess;
propertiesCache.clear();
readableProperties.clear();
}
}
public void setAllowReadOnlyProperties(boolean allowReadOnlyProperties) {
if (this.allowReadOnlyProperties != allowReadOnlyProperties) {
this.allowReadOnlyProperties = allowReadOnlyProperties;
readableProperties.clear();
}
}
public boolean isAllowReadOnlyProperties() {
return allowReadOnlyProperties;
}
/**
* Skip properties that are missing during deserialization of YAML to a Java
* object. The default is false.
*
* @param skipMissingProperties
* true if missing properties should be skipped, false otherwise.
*/
public void setSkipMissingProperties(boolean skipMissingProperties) {
if (this.skipMissingProperties != skipMissingProperties) {
this.skipMissingProperties = skipMissingProperties;
readableProperties.clear();
}
}
public boolean isSkipMissingProperties() {
return skipMissingProperties;
}
}