commons-vfs2/src/main/java/org/apache/commons/vfs2/util/DelegatingFileSystemOptionsBuilder.java - commons-vfs - Git at Google

 /*
  * 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.commons.vfs2.util;

 import java.lang.reflect.Array;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;

 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.commons.vfs2.FileSystemConfigBuilder;
 import org.apache.commons.vfs2.FileSystemException;
 import org.apache.commons.vfs2.FileSystemManager;
 import org.apache.commons.vfs2.FileSystemOptions;

 /**
  * This class use reflection to set a configuration value using the fileSystemConfigBuilder associated the a scheme.
  * <p>
  * Example:
  * </p>
  *
  * <pre>
  * FileSystemOptions fso = new FileSystemOptions();
  * DelegatingFileSystemOptionsBuilder delegate = new DelegatingFileSystemOptionsBuilder(VFS.getManager());
  * delegate.setConfigString(fso, "sftp", "identities", "c:/tmp/test.ident");
  * delegate.setConfigString(fso, "http", "proxyPort", "8080");
  * delegate.setConfigClass(fso, "sftp", "userinfo", TrustEveryoneUserInfo.class);
  * </pre>
  */
 public class DelegatingFileSystemOptionsBuilder {

     @SuppressWarnings("unchecked") // OK, it is a String
     private static final Class<String>[] STRING_PARAM = new Class[] { String.class };
     private static final Map<String, Class<?>> PRIMATIVE_TO_OBJECT = new TreeMap<>();
     private static final Log log = LogFactory.getLog(DelegatingFileSystemOptionsBuilder.class);

     private final FileSystemManager manager;
     private final Map<String, Map<String, List<Method>>> beanMethods = new TreeMap<>();

     static {
         PRIMATIVE_TO_OBJECT.put(Void.TYPE.getName(), Void.class);
         PRIMATIVE_TO_OBJECT.put(Boolean.TYPE.getName(), Boolean.class);
         PRIMATIVE_TO_OBJECT.put(Byte.TYPE.getName(), Byte.class);
         PRIMATIVE_TO_OBJECT.put(Character.TYPE.getName(), Character.class);
         PRIMATIVE_TO_OBJECT.put(Short.TYPE.getName(), Short.class);
         PRIMATIVE_TO_OBJECT.put(Integer.TYPE.getName(), Integer.class);
         PRIMATIVE_TO_OBJECT.put(Long.TYPE.getName(), Long.class);
         PRIMATIVE_TO_OBJECT.put(Double.TYPE.getName(), Double.class);
         PRIMATIVE_TO_OBJECT.put(Float.TYPE.getName(), Float.class);
     }

     /**
      * Context.
      */
     private static final class Context {
         private final FileSystemOptions fso;
         private final String scheme;
         private final String name;
         private final Object[] values;

         private List<Method> configSetters;
         private FileSystemConfigBuilder fileSystemConfigBuilder;

         private Context(final FileSystemOptions fso, final String scheme, final String name, final Object[] values) {
             this.fso = fso;
             this.scheme = scheme;
             this.name = name;
             this.values = values;
         }
     }

     /**
      * Constructor.
      * <p>
      * Pass in your fileSystemManager instance.
      * </p>
      *
      * @param manager the manager to use to get the fileSystemConfigBuilder assocated to a scheme
      */
     public DelegatingFileSystemOptionsBuilder(final FileSystemManager manager) {
         this.manager = manager;
     }

     protected FileSystemManager getManager() {
         return manager;
     }

     /**
      * Sets a single string value.
      *
      * @param fso FileSystemOptions
      * @param scheme scheme
      * @param name name
      * @param value value
      * @throws FileSystemException if an error occurs.
      */
     public void setConfigString(final FileSystemOptions fso, final String scheme, final String name, final String value)
             throws FileSystemException {
         setConfigStrings(fso, scheme, name, new String[] { value });
     }

     /**
      * Sets an array of string value.
      *
      * @param fso FileSystemOptions
      * @param scheme scheme
      * @param name name
      * @param values values
      * @throws FileSystemException if an error occurs.
      */
     public void setConfigStrings(final FileSystemOptions fso, final String scheme, final String name,
             final String[] values) throws FileSystemException {
         final Context ctx = new Context(fso, scheme, name, values);

         setValues(ctx);
     }

     /**
      * Sets a single class value.
      * <p>
      * The class has to implement a no-args constructor, else the instantiation might fail.
      * </p>
      *
      * @param fso FileSystemOptions
      * @param scheme scheme
      * @param name name
      * @param className className
      * @throws FileSystemException if an error occurs.
      * @throws IllegalAccessException if a class canoot be accessed.
      * @throws InstantiationException if a class cannot be instantiated.
      */
     public void setConfigClass(final FileSystemOptions fso, final String scheme, final String name,
             final Class<?> className) throws FileSystemException, IllegalAccessException, InstantiationException {
         setConfigClasses(fso, scheme, name, new Class[] { className });
     }

     /**
      * Sets an array of class values.
      * <p>
      * The class has to implement a no-args constructor, else the instantiation might fail.
      * </p>
      *
      * @param fso FileSystemOptions
      * @param scheme scheme
      * @param name name
      * @param classNames classNames
      * @throws FileSystemException if an error occurs.
      * @throws IllegalAccessException if a class canoot be accessed.
      * @throws InstantiationException if a class cannot be instantiated.
      */
     public void setConfigClasses(final FileSystemOptions fso, final String scheme, final String name,
             final Class<?>[] classNames) throws FileSystemException, IllegalAccessException, InstantiationException {
         final Object[] values = new Object[classNames.length];
         for (int iterClassNames = 0; iterClassNames < values.length; iterClassNames++) {
             values[iterClassNames] = classNames[iterClassNames].newInstance();
         }

         final Context ctx = new Context(fso, scheme, name, values);

         setValues(ctx);
     }

     /**
      * Sets the values using the informations of the given context.
      */
     private void setValues(final Context ctx) throws FileSystemException {
         // find all setter methods suitable for the given "name"
         if (!fillConfigSetters(ctx)) {
             throw new FileSystemException("vfs.provider/config-key-invalid.error", ctx.scheme, ctx.name);
         }

         // get the fileSystemConfigBuilder
         ctx.fileSystemConfigBuilder = getManager().getFileSystemConfigBuilder(ctx.scheme);

         // try to find a setter which could accept the value
         for (final Method configSetter : ctx.configSetters) {
             if (convertValuesAndInvoke(configSetter, ctx)) {
                 return;
             }
         }

         throw new FileSystemException("vfs.provider/config-value-invalid.error", ctx.scheme, ctx.name, ctx.values);
     }

     /**
      * Tries to convert the value and pass it to the given method
      */
     private boolean convertValuesAndInvoke(final Method configSetter, final Context ctx) throws FileSystemException {
         final Class<?>[] parameters = configSetter.getParameterTypes();
         if (parameters.length < 2) {
             return false;
         }
         if (!parameters[0].isAssignableFrom(FileSystemOptions.class)) {
             return false;
         }

         final Class<?> valueParameter = parameters[1];
         Class<?> type;
         if (valueParameter.isArray()) {
             type = valueParameter.getComponentType();
         } else {
             if (ctx.values.length > 1) {
                 return false;
             }

             type = valueParameter;
         }

         if (type.isPrimitive()) {
             final Class<?> objectType = PRIMATIVE_TO_OBJECT.get(type.getName());
             if (objectType == null) {
                 log.warn(Messages.getString("vfs.provider/config-unexpected-primitive.error", type.getName()));
                 return false;
             }
             type = objectType;
         }

         final Class<? extends Object> valueClass = ctx.values[0].getClass();
         if (type.isAssignableFrom(valueClass)) {
             // can set value directly
             invokeSetter(valueParameter, ctx, configSetter, ctx.values);
             return true;
         }
         if (valueClass != String.class) {
             log.warn(Messages.getString("vfs.provider/config-unexpected-value-class.error", valueClass.getName(),
                     ctx.scheme, ctx.name));
             return false;
         }

         final Object convertedValues = Array.newInstance(type, ctx.values.length);

         Constructor<?> valueConstructor;
         try {
             valueConstructor = type.getConstructor(STRING_PARAM);
         } catch (final NoSuchMethodException e) {
             valueConstructor = null;
         }
         if (valueConstructor != null) {
             // can convert using constructor
             for (int iterValues = 0; iterValues < ctx.values.length; iterValues++) {
                 try {
                     Array.set(convertedValues, iterValues, valueConstructor.newInstance(ctx.values[iterValues]));
                 } catch (final InstantiationException | IllegalAccessException | InvocationTargetException e) {
                     throw new FileSystemException(e);
                 }
             }

             invokeSetter(valueParameter, ctx, configSetter, convertedValues);
             return true;
         }

         Method valueFactory;
         try {
             valueFactory = type.getMethod("valueOf", STRING_PARAM);
             if (!Modifier.isStatic(valueFactory.getModifiers())) {
                 valueFactory = null;
             }
         } catch (final NoSuchMethodException e) {
             valueFactory = null;
         }

         if (valueFactory != null) {
             // can convert using factory method (valueOf)
             for (int iterValues = 0; iterValues < ctx.values.length; iterValues++) {
                 try {
                     Array.set(convertedValues, iterValues,
                             valueFactory.invoke(null, ctx.values[iterValues]));
                 } catch (final IllegalAccessException | InvocationTargetException e) {
                     throw new FileSystemException(e);
                 }
             }

             invokeSetter(valueParameter, ctx, configSetter, convertedValues);
             return true;
         }

         return false;
     }

     /**
      * Invokes the method with the converted values
      */
     private void invokeSetter(final Class<?> valueParameter, final Context ctx, final Method configSetter,
             final Object values) throws FileSystemException {
         final Object[] args;
         if (valueParameter.isArray()) {
             args = new Object[] { ctx.fso, values };
         } else {
             args = new Object[] { ctx.fso, Array.get(values, 0) };
         }
         try {
             configSetter.invoke(ctx.fileSystemConfigBuilder, args);
         } catch (final IllegalAccessException | InvocationTargetException e) {
             throw new FileSystemException(e);
         }
     }

     /**
      * Fills all available set*() methods for the context-scheme into the context.
      */
     private boolean fillConfigSetters(final Context ctx) throws FileSystemException {
         final Map<String, List<Method>> schemeMethods = getSchemeMethods(ctx.scheme);
         final List<Method> configSetters = schemeMethods.get(ctx.name.toLowerCase());
         if (configSetters == null) {
             return false;
         }

         ctx.configSetters = configSetters;
         return true;
     }

     /**
      * Gets (cached) list of set*() methods for the given scheme
      */
     private Map<String, List<Method>> getSchemeMethods(final String scheme) throws FileSystemException {
         Map<String, List<Method>> schemeMethods = beanMethods.get(scheme);
         if (schemeMethods == null) {
             schemeMethods = createSchemeMethods(scheme);
             beanMethods.put(scheme, schemeMethods);
         }

         return schemeMethods;
     }

     /**
      * Creates the list of all set*() methods for the given scheme
      */
     private Map<String, List<Method>> createSchemeMethods(final String scheme) throws FileSystemException {
         final FileSystemConfigBuilder fscb = getManager().getFileSystemConfigBuilder(scheme);
         FileSystemException.requireNonNull(fscb, "vfs.provider/no-config-builder.error", scheme);

         final Map<String, List<Method>> schemeMethods = new TreeMap<>();

         final Method[] methods = fscb.getClass().getMethods();
         for (final Method method : methods) {
             if (!Modifier.isPublic(method.getModifiers())) {
                 continue;
             }

             final String methodName = method.getName();
             if (!methodName.startsWith("set")) {
                 // not a setter
                 continue;
             }

             final String key = methodName.substring(3).toLowerCase();

             final List<Method> configSetter = schemeMethods.computeIfAbsent(key, k -> new ArrayList<>(2));
             configSetter.add(method);
         }

         return schemeMethods;
     }
 }
	/*
	* 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.commons.vfs2.util;

	import java.lang.reflect.Array;
	import java.lang.reflect.Constructor;
	import java.lang.reflect.InvocationTargetException;
	import java.lang.reflect.Method;
	import java.lang.reflect.Modifier;
	import java.util.ArrayList;
	import java.util.List;
	import java.util.Map;
	import java.util.TreeMap;

	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;
	import org.apache.commons.vfs2.FileSystemConfigBuilder;
	import org.apache.commons.vfs2.FileSystemException;
	import org.apache.commons.vfs2.FileSystemManager;
	import org.apache.commons.vfs2.FileSystemOptions;

	/**
	* This class use reflection to set a configuration value using the fileSystemConfigBuilder associated the a scheme.
	* <p>
	* Example:
	* </p>
	*
	* <pre>
	* FileSystemOptions fso = new FileSystemOptions();
	* DelegatingFileSystemOptionsBuilder delegate = new DelegatingFileSystemOptionsBuilder(VFS.getManager());
	* delegate.setConfigString(fso, "sftp", "identities", "c:/tmp/test.ident");
	* delegate.setConfigString(fso, "http", "proxyPort", "8080");
	* delegate.setConfigClass(fso, "sftp", "userinfo", TrustEveryoneUserInfo.class);
	* </pre>
	*/
	public class DelegatingFileSystemOptionsBuilder {

	@SuppressWarnings("unchecked") // OK, it is a String
	private static final Class<String>[] STRING_PARAM = new Class[] { String.class };
	private static final Map<String, Class<?>> PRIMATIVE_TO_OBJECT = new TreeMap<>();
	private static final Log log = LogFactory.getLog(DelegatingFileSystemOptionsBuilder.class);

	private final FileSystemManager manager;
	private final Map<String, Map<String, List<Method>>> beanMethods = new TreeMap<>();

	static {
	PRIMATIVE_TO_OBJECT.put(Void.TYPE.getName(), Void.class);
	PRIMATIVE_TO_OBJECT.put(Boolean.TYPE.getName(), Boolean.class);
	PRIMATIVE_TO_OBJECT.put(Byte.TYPE.getName(), Byte.class);
	PRIMATIVE_TO_OBJECT.put(Character.TYPE.getName(), Character.class);
	PRIMATIVE_TO_OBJECT.put(Short.TYPE.getName(), Short.class);
	PRIMATIVE_TO_OBJECT.put(Integer.TYPE.getName(), Integer.class);
	PRIMATIVE_TO_OBJECT.put(Long.TYPE.getName(), Long.class);
	PRIMATIVE_TO_OBJECT.put(Double.TYPE.getName(), Double.class);
	PRIMATIVE_TO_OBJECT.put(Float.TYPE.getName(), Float.class);
	}

	/**
	* Context.
	*/
	private static final class Context {
	private final FileSystemOptions fso;
	private final String scheme;
	private final String name;
	private final Object[] values;

	private List<Method> configSetters;
	private FileSystemConfigBuilder fileSystemConfigBuilder;

	private Context(final FileSystemOptions fso, final String scheme, final String name, final Object[] values) {
	this.fso = fso;
	this.scheme = scheme;
	this.name = name;
	this.values = values;
	}
	}

	/**
	* Constructor.
	* <p>
	* Pass in your fileSystemManager instance.
	* </p>
	*
	* @param manager the manager to use to get the fileSystemConfigBuilder assocated to a scheme
	*/
	public DelegatingFileSystemOptionsBuilder(final FileSystemManager manager) {
	this.manager = manager;
	}

	protected FileSystemManager getManager() {
	return manager;
	}

	/**
	* Sets a single string value.
	*
	* @param fso FileSystemOptions
	* @param scheme scheme
	* @param name name
	* @param value value
	* @throws FileSystemException if an error occurs.
	*/
	public void setConfigString(final FileSystemOptions fso, final String scheme, final String name, final String value)
	throws FileSystemException {
	setConfigStrings(fso, scheme, name, new String[] { value });
	}

	/**
	* Sets an array of string value.
	*
	* @param fso FileSystemOptions
	* @param scheme scheme
	* @param name name
	* @param values values
	* @throws FileSystemException if an error occurs.
	*/
	public void setConfigStrings(final FileSystemOptions fso, final String scheme, final String name,
	final String[] values) throws FileSystemException {
	final Context ctx = new Context(fso, scheme, name, values);

	setValues(ctx);
	}

	/**
	* Sets a single class value.
	* <p>
	* The class has to implement a no-args constructor, else the instantiation might fail.
	* </p>
	*
	* @param fso FileSystemOptions
	* @param scheme scheme
	* @param name name
	* @param className className
	* @throws FileSystemException if an error occurs.
	* @throws IllegalAccessException if a class canoot be accessed.
	* @throws InstantiationException if a class cannot be instantiated.
	*/
	public void setConfigClass(final FileSystemOptions fso, final String scheme, final String name,
	final Class<?> className) throws FileSystemException, IllegalAccessException, InstantiationException {
	setConfigClasses(fso, scheme, name, new Class[] { className });
	}

	/**
	* Sets an array of class values.
	* <p>
	* The class has to implement a no-args constructor, else the instantiation might fail.
	* </p>
	*
	* @param fso FileSystemOptions
	* @param scheme scheme
	* @param name name
	* @param classNames classNames
	* @throws FileSystemException if an error occurs.
	* @throws IllegalAccessException if a class canoot be accessed.
	* @throws InstantiationException if a class cannot be instantiated.
	*/
	public void setConfigClasses(final FileSystemOptions fso, final String scheme, final String name,
	final Class<?>[] classNames) throws FileSystemException, IllegalAccessException, InstantiationException {
	final Object[] values = new Object[classNames.length];
	for (int iterClassNames = 0; iterClassNames < values.length; iterClassNames++) {
	values[iterClassNames] = classNames[iterClassNames].newInstance();
	}

	final Context ctx = new Context(fso, scheme, name, values);

	setValues(ctx);
	}

	/**
	* Sets the values using the informations of the given context.
	*/
	private void setValues(final Context ctx) throws FileSystemException {
	// find all setter methods suitable for the given "name"
	if (!fillConfigSetters(ctx)) {
	throw new FileSystemException("vfs.provider/config-key-invalid.error", ctx.scheme, ctx.name);
	}

	// get the fileSystemConfigBuilder
	ctx.fileSystemConfigBuilder = getManager().getFileSystemConfigBuilder(ctx.scheme);

	// try to find a setter which could accept the value
	for (final Method configSetter : ctx.configSetters) {
	if (convertValuesAndInvoke(configSetter, ctx)) {
	return;
	}
	}

	throw new FileSystemException("vfs.provider/config-value-invalid.error", ctx.scheme, ctx.name, ctx.values);
	}

	/**
	* Tries to convert the value and pass it to the given method
	*/
	private boolean convertValuesAndInvoke(final Method configSetter, final Context ctx) throws FileSystemException {
	final Class<?>[] parameters = configSetter.getParameterTypes();
	if (parameters.length < 2) {
	return false;
	}
	if (!parameters[0].isAssignableFrom(FileSystemOptions.class)) {
	return false;
	}

	final Class<?> valueParameter = parameters[1];
	Class<?> type;
	if (valueParameter.isArray()) {
	type = valueParameter.getComponentType();
	} else {
	if (ctx.values.length > 1) {
	return false;
	}

	type = valueParameter;
	}

	if (type.isPrimitive()) {
	final Class<?> objectType = PRIMATIVE_TO_OBJECT.get(type.getName());
	if (objectType == null) {
	log.warn(Messages.getString("vfs.provider/config-unexpected-primitive.error", type.getName()));
	return false;
	}
	type = objectType;
	}

	final Class<? extends Object> valueClass = ctx.values[0].getClass();
	if (type.isAssignableFrom(valueClass)) {
	// can set value directly
	invokeSetter(valueParameter, ctx, configSetter, ctx.values);
	return true;
	}
	if (valueClass != String.class) {
	log.warn(Messages.getString("vfs.provider/config-unexpected-value-class.error", valueClass.getName(),
	ctx.scheme, ctx.name));
	return false;
	}

	final Object convertedValues = Array.newInstance(type, ctx.values.length);

	Constructor<?> valueConstructor;
	try {
	valueConstructor = type.getConstructor(STRING_PARAM);
	} catch (final NoSuchMethodException e) {
	valueConstructor = null;
	}
	if (valueConstructor != null) {
	// can convert using constructor
	for (int iterValues = 0; iterValues < ctx.values.length; iterValues++) {
	try {
	Array.set(convertedValues, iterValues, valueConstructor.newInstance(ctx.values[iterValues]));
	} catch (final InstantiationException \| IllegalAccessException \| InvocationTargetException e) {
	throw new FileSystemException(e);
	}
	}

	invokeSetter(valueParameter, ctx, configSetter, convertedValues);
	return true;
	}

	Method valueFactory;
	try {
	valueFactory = type.getMethod("valueOf", STRING_PARAM);
	if (!Modifier.isStatic(valueFactory.getModifiers())) {
	valueFactory = null;
	}
	} catch (final NoSuchMethodException e) {
	valueFactory = null;
	}

	if (valueFactory != null) {
	// can convert using factory method (valueOf)
	for (int iterValues = 0; iterValues < ctx.values.length; iterValues++) {
	try {
	Array.set(convertedValues, iterValues,
	valueFactory.invoke(null, ctx.values[iterValues]));
	} catch (final IllegalAccessException \| InvocationTargetException e) {
	throw new FileSystemException(e);
	}
	}

	invokeSetter(valueParameter, ctx, configSetter, convertedValues);
	return true;
	}

	return false;
	}

	/**
	* Invokes the method with the converted values
	*/
	private void invokeSetter(final Class<?> valueParameter, final Context ctx, final Method configSetter,
	final Object values) throws FileSystemException {
	final Object[] args;
	if (valueParameter.isArray()) {
	args = new Object[] { ctx.fso, values };
	} else {
	args = new Object[] { ctx.fso, Array.get(values, 0) };
	}
	try {
	configSetter.invoke(ctx.fileSystemConfigBuilder, args);
	} catch (final IllegalAccessException \| InvocationTargetException e) {
	throw new FileSystemException(e);
	}
	}

	/**
	* Fills all available set*() methods for the context-scheme into the context.
	*/
	private boolean fillConfigSetters(final Context ctx) throws FileSystemException {
	final Map<String, List<Method>> schemeMethods = getSchemeMethods(ctx.scheme);
	final List<Method> configSetters = schemeMethods.get(ctx.name.toLowerCase());
	if (configSetters == null) {
	return false;
	}

	ctx.configSetters = configSetters;
	return true;
	}

	/**
	* Gets (cached) list of set*() methods for the given scheme
	*/
	private Map<String, List<Method>> getSchemeMethods(final String scheme) throws FileSystemException {
	Map<String, List<Method>> schemeMethods = beanMethods.get(scheme);
	if (schemeMethods == null) {
	schemeMethods = createSchemeMethods(scheme);
	beanMethods.put(scheme, schemeMethods);
	}

	return schemeMethods;
	}

	/**
	* Creates the list of all set*() methods for the given scheme
	*/
	private Map<String, List<Method>> createSchemeMethods(final String scheme) throws FileSystemException {
	final FileSystemConfigBuilder fscb = getManager().getFileSystemConfigBuilder(scheme);
	FileSystemException.requireNonNull(fscb, "vfs.provider/no-config-builder.error", scheme);

	final Map<String, List<Method>> schemeMethods = new TreeMap<>();

	final Method[] methods = fscb.getClass().getMethods();
	for (final Method method : methods) {
	if (!Modifier.isPublic(method.getModifiers())) {
	continue;
	}

	final String methodName = method.getName();
	if (!methodName.startsWith("set")) {
	// not a setter
	continue;
	}

	final String key = methodName.substring(3).toLowerCase();

	final List<Method> configSetter = schemeMethods.computeIfAbsent(key, k -> new ArrayList<>(2));
	configSetter.add(method);
	}

	return schemeMethods;
	}
	}