/*
* Copyright 2002-2016 the original author or authors.
*
* 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.springframework.core.io.support;
import java.beans.PropertyEditorSupport;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.env.Environment;
import org.springframework.core.env.PropertyResolver;
import org.springframework.core.env.StandardEnvironment;
import org.springframework.core.io.Resource;
import org.springframework.util.Assert;
/**
* Editor for {@link org.springframework.core.io.Resource} arrays, to
* automatically convert {@code String} location patterns
* (e.g. {@code "file:C:/my*.txt"} or {@code "classpath*:myfile.txt"})
* to {@code Resource} array properties. Can also translate a collection
* or array of location patterns into a merged Resource array.
*
* <p>A path may contain {@code ${...}} placeholders, to be
* resolved as {@link org.springframework.core.env.Environment} properties:
* e.g. {@code ${user.dir}}. Unresolvable placeholders are ignored by default.
*
* <p>Delegates to a {@link ResourcePatternResolver},
* by default using a {@link PathMatchingResourcePatternResolver}.
*
* @author Juergen Hoeller
* @author Chris Beams
* @since 1.1.2
* @see org.springframework.core.io.Resource
* @see ResourcePatternResolver
* @see PathMatchingResourcePatternResolver
*/
public class ResourceArrayPropertyEditor extends PropertyEditorSupport {
private static final Log logger = LogFactory.getLog(ResourceArrayPropertyEditor.class);
private final ResourcePatternResolver resourcePatternResolver;
private PropertyResolver propertyResolver;
private final boolean ignoreUnresolvablePlaceholders;
/**
* Create a new ResourceArrayPropertyEditor with a default
* {@link PathMatchingResourcePatternResolver} and {@link StandardEnvironment}.
* @see PathMatchingResourcePatternResolver
* @see Environment
*/
public ResourceArrayPropertyEditor() {
this(new PathMatchingResourcePatternResolver(), null, true);
}
/**
* Create a new ResourceArrayPropertyEditor with the given {@link ResourcePatternResolver}
* and {@link PropertyResolver} (typically an {@link Environment}).
* @param resourcePatternResolver the ResourcePatternResolver to use
* @param propertyResolver the PropertyResolver to use
*/
public ResourceArrayPropertyEditor(ResourcePatternResolver resourcePatternResolver, PropertyResolver propertyResolver) {
this(resourcePatternResolver, propertyResolver, true);
}
/**
* Create a new ResourceArrayPropertyEditor with the given {@link ResourcePatternResolver}
* and {@link PropertyResolver} (typically an {@link Environment}).
* @param resourcePatternResolver the ResourcePatternResolver to use
* @param propertyResolver the PropertyResolver to use
* @param ignoreUnresolvablePlaceholders whether to ignore unresolvable placeholders
* if no corresponding system property could be found
*/
public ResourceArrayPropertyEditor(ResourcePatternResolver resourcePatternResolver,
PropertyResolver propertyResolver, boolean ignoreUnresolvablePlaceholders) {
Assert.notNull(resourcePatternResolver, "ResourcePatternResolver must not be null");
this.resourcePatternResolver = resourcePatternResolver;
this.propertyResolver = propertyResolver;
this.ignoreUnresolvablePlaceholders = ignoreUnresolvablePlaceholders;
}
/**
* Treat the given text as a location pattern and convert it to a Resource array.
*/
@Override
public void setAsText(String text) {
String pattern = resolvePath(text).trim();
try {
setValue(this.resourcePatternResolver.getResources(pattern));
}
catch (IOException ex) {
throw new IllegalArgumentException(
"Could not resolve resource location pattern [" + pattern + "]: " + ex.getMessage());
}
}
/**
* Treat the given value as a collection or array and convert it to a Resource array.
* Considers String elements as location patterns and takes Resource elements as-is.
*/
@Override
public void setValue(Object value) throws IllegalArgumentException {
if (value instanceof Collection || (value instanceof Object[] && !(value instanceof Resource[]))) {
Collection<?> input = (value instanceof Collection ? (Collection<?>) value : Arrays.asList((Object[]) value));
List<Resource> merged = new ArrayList<>();
for (Object element : input) {
if (element instanceof String) {
// A location pattern: resolve it into a Resource array.
// Might point to a single resource or to multiple resources.
String pattern = resolvePath((String) element).trim();
try {
Resource[] resources = this.resourcePatternResolver.getResources(pattern);
for (Resource resource : resources) {
if (!merged.contains(resource)) {
merged.add(resource);
}
}
}
catch (IOException ex) {
// ignore - might be an unresolved placeholder or non-existing base directory
if (logger.isDebugEnabled()) {
logger.debug("Could not retrieve resources for pattern '" + pattern + "'", ex);
}
}
}
else if (element instanceof Resource) {
// A Resource object: add it to the result.
Resource resource = (Resource) element;
if (!merged.contains(resource)) {
merged.add(resource);
}
}
else {
throw new IllegalArgumentException("Cannot convert element [" + element + "] to [" +
Resource.class.getName() + "]: only location String and Resource object supported");
}
}
super.setValue(merged.toArray(new Resource[merged.size()]));
}
else {
// An arbitrary value: probably a String or a Resource array.
// setAsText will be called for a String; a Resource array will be used as-is.
super.setValue(value);
}
}
/**
* Resolve the given path, replacing placeholders with
* corresponding system property values if necessary.
* @param path the original file path
* @return the resolved file path
* @see PropertyResolver#resolvePlaceholders
* @see PropertyResolver#resolveRequiredPlaceholders(String)
*/
protected String resolvePath(String path) {
if (this.propertyResolver == null) {
this.propertyResolver = new StandardEnvironment();
}
return (this.ignoreUnresolvablePlaceholders ? this.propertyResolver.resolvePlaceholders(path) :
this.propertyResolver.resolveRequiredPlaceholders(path));
}
}