org.yaml.snakeyaml.introspector.PropertyUtils Maven / Gradle / Ivy
/**
* 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.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 org.yaml.snakeyaml.error.YAMLException;
import org.yaml.snakeyaml.util.PlatformFeatureDetector;
public class PropertyUtils {
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 static final String TRANSIENT = "transient";
private boolean isTransient(FeatureDescriptor fd) {
return Boolean.TRUE.equals(fd.getValue(TRANSIENT));
}
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;
}
}