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/* * 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; /** * Abstract class which has the right to fill FileSystemOptions. */ public abstract class FileSystemConfigBuilder { /** Default prefix to use when resolving system properties */ private static final String PREFIX = "vfs."; /** The root uri of the file system */ private static final String ROOTURI = "rootURI"; /** The prefix to use when resolving system properties */ private final String prefix; /** * Construct builder with default prefix. * * @since 1.0 */ protected FileSystemConfigBuilder() { this.prefix = PREFIX; } /** * Construct builder with specified component name. * * @param component component name to be used in prefix * * @since 2.0 */ protected FileSystemConfigBuilder(final String component) { this.prefix = PREFIX + component; } /** * The root URI of the file system. * * @param opts the file system options to modify * @param rootURI The creator name to be associated with the file. * * @since 2.0 */ public void setRootURI(final FileSystemOptions opts, final String rootURI) { setParam(opts, ROOTURI, rootURI); } /** * Return the root URI of the file system. * * @param opts file system options to work with * @return The root URI * * @since 2.0 */ public String getRootURI(final FileSystemOptions opts) { return getString(opts, ROOTURI); } /** * Set named parameter. * * @param opts the file system options to modify * @param name set option with this name * @param value boolean value to set * * @since 2.1 */ protected void setParam(final FileSystemOptions opts, final String name, final boolean value) { setParam(opts, name, Boolean.valueOf(value)); } /** * Set named parameter. * * @param opts the file system options to modify * @param name set option with this name * @param value object value to set * * @since 1.0 */ protected void setParam(final FileSystemOptions opts, final String name, final Object value) { opts.setOption(getConfigClass(), name, value); } /** * Get named parameter. * * @param opts file system options to work with * @param name get option with this name * @return the named option or null * * @since 1.0 */ protected Object getParam(final FileSystemOptions opts, final String name) { if (opts == null) { return null; } return opts.getOption(getConfigClass(), name); } /** * Check if option exists. * * @param opts file system options to work with * @param name the name to look up in {@code opts} * @return true if opts have the named parameter * * @since 1.0 */ protected boolean hasParam(final FileSystemOptions opts, final String name) { return opts != null && opts.hasOption(getConfigClass(), name); } /** * Is named setting specified. * * @param opts file system options to work with * @param name the option to check in {@code opts} or system properties * @return true if option exists * * @since 2.0 */ protected boolean hasObject(final FileSystemOptions opts, final String name) { return hasParam(opts, name) || System.getProperties().containsKey(toPropertyKey(name)); } /** * Get named option as boolean. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getBoolean(FileSystemOptions, String, Boolean) * * @since 2.0 */ protected Boolean getBoolean(final FileSystemOptions opts, final String name) { return getBoolean(opts, name, null); } /** * Get named option as boolean. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getBoolean(FileSystemOptions, String, Boolean) * * @since 2.0 */ protected boolean getBoolean(final FileSystemOptions opts, final String name, final boolean defaultValue) { return getBoolean(opts, name, Boolean.valueOf(defaultValue)).booleanValue(); } /** * Get named option as boolean. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getBoolean(FileSystemOptions, String, Boolean) * * @since 2.0 */ protected Boolean getBoolean(final FileSystemOptions opts, final String name, final Boolean defaultValue) { Boolean value = (Boolean) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null) { return defaultValue; } value = Boolean.valueOf(str); } return value; } /** * Get named option as byte. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getByte(FileSystemOptions, String, Byte) * * @since 2.0 */ protected Byte getByte(final FileSystemOptions opts, final String name) { return getByte(opts, name, null); } /** * Get named option as byte. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getByte(FileSystemOptions, String, Byte) * * @since 2.0 */ protected byte getByte(final FileSystemOptions opts, final String name, final byte defaultValue) { return getByte(opts, name, Byte.valueOf(defaultValue)).byteValue(); } /** * Get named option as byte. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * * @since 2.0 */ protected Byte getByte(final FileSystemOptions opts, final String name, final Byte defaultValue) { Byte value = (Byte) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null) { return defaultValue; } value = Byte.valueOf(str); } return value; } /** * Get named option as character. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getCharacter(FileSystemOptions, String, Character) * * @since 2.0 */ protected Character getCharacter(final FileSystemOptions opts, final String name) { return getCharacter(opts, name, null); } /** * Get named option as character. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getCharacter(FileSystemOptions, String, Character) * * @since 2.0 */ protected char getCharacter(final FileSystemOptions opts, final String name, final char defaultValue) { return getCharacter(opts, name, new Character(defaultValue)).charValue(); } /** * Get named option as character. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * * @since 2.0 */ protected Character getCharacter(final FileSystemOptions opts, final String name, final Character defaultValue) { Character value = (Character) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null || str.length() <= 0) { return defaultValue; } value = new Character(str.charAt(0)); } return value; } /** * Get named option as double. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getDouble(FileSystemOptions, String, Double) * * @since 2.0 */ protected Double getDouble(final FileSystemOptions opts, final String name) { return getDouble(opts, name, null); } /** * Get named option as double. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getDouble(FileSystemOptions, String, Double) * * @since 2.0 */ protected double getDouble(final FileSystemOptions opts, final String name, final double defaultValue) { return getDouble(opts, name, new Double(defaultValue)).doubleValue(); } /** * Get named option as double. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * * @since 2.0 */ protected Double getDouble(final FileSystemOptions opts, final String name, final Double defaultValue) { Double value = (Double) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null || str.length() <= 0) { return defaultValue; } value = Double.valueOf(str); } return value; } /** * Get named option as enumeration. * * @param <E> enumeration type * @param enumClass class of enumeration type * @param opts file system options to work with * @param name the option name * * @return the option in {@code opts} or system properties, otherwise null * @see #getEnum(Class, FileSystemOptions, String, Enum) * @throws IllegalArgumentException if option value is not a known enumeration. * * @since 2.1 */ protected <E extends Enum<E>> E getEnum(final Class<E> enumClass, final FileSystemOptions opts, final String name) { return this.<E>getEnum(enumClass, opts, name, null); } /** * Get named option as enumeration. * * @param <E> enumeration type * @param enumClass class of enumeration type * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getEnum(Class, FileSystemOptions, String, Enum) * @throws IllegalArgumentException if option value is not a known enumeration. * * @since 2.1 */ protected <E extends Enum<E>> E getEnum(final Class<E> enumClass, final FileSystemOptions opts, final String name, final E defaultValue) { @SuppressWarnings("unchecked") E value = (E) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null) { return defaultValue; } value = Enum.valueOf(enumClass, str); } return value; } /** * Get named option as float. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getFloat(FileSystemOptions, String, Float) * @throws NumberFormatException if option value is not a valid float. * * @since 2.0 */ protected Float getFloat(final FileSystemOptions opts, final String name) { return getFloat(opts, name, null); } /** * Get named option as float. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getFloat(FileSystemOptions, String, Float) * @throws NumberFormatException if option value is not a valid float. * * @since 2.0 */ protected float getFloat(final FileSystemOptions opts, final String name, final float defaultValue) { return getFloat(opts, name, new Float(defaultValue)).floatValue(); } /** * Get named option as float. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @throws NumberFormatException if option value is not a valid float. * * @since 2.0 */ protected Float getFloat(final FileSystemOptions opts, final String name, final Float defaultValue) { Float value = (Float) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null || str.length() <= 0) { return defaultValue; } value = Float.valueOf(str); } return value; } /** * Get named option as integer. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getInteger(FileSystemOptions, String, Integer) * @throws NumberFormatException if option value is not a valid integer. * * @since 2.0 */ protected Integer getInteger(final FileSystemOptions opts, final String name) { return getInteger(opts, name, null); } /** * Get named option as integer. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getInteger(FileSystemOptions, String, Integer) * @throws NumberFormatException if option value is not a valid integer. * * @since 2.0 */ protected int getInteger(final FileSystemOptions opts, final String name, final int defaultValue) { return getInteger(opts, name, Integer.valueOf(defaultValue)).intValue(); } /** * Get named option as integer. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @throws NumberFormatException if option value is not a valid integer. * * @since 2.0 */ protected Integer getInteger(final FileSystemOptions opts, final String name, final Integer defaultValue) { Integer value = (Integer) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null) { return defaultValue; } value = Integer.valueOf(str); } return value; } /** * Get named option as long. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getLong(FileSystemOptions, String, Long) * @throws NumberFormatException if option value is not a valid long. * * @since 2.0 */ protected Long getLong(final FileSystemOptions opts, final String name) { return getLong(opts, name, null); } /** * Get named option as long. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getLong(FileSystemOptions, String, Long) * @throws NumberFormatException if option value is not a valid long. * * @since 2.0 */ protected long getLong(final FileSystemOptions opts, final String name, final long defaultValue) { return getLong(opts, name, Long.valueOf(defaultValue)).longValue(); } /** * Get named option as long. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @throws NumberFormatException if option value is not a valid long. * * @since 2.0 */ protected Long getLong(final FileSystemOptions opts, final String name, final Long defaultValue) { Long value = (Long) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null) { return defaultValue; } value = Long.valueOf(str); } return value; } /** * Get named option as short. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getShort(FileSystemOptions, String, Short) * @throws NumberFormatException if option value is not a valid short. * * @since 2.0 */ protected Short getShort(final FileSystemOptions opts, final String name) { return getShort(opts, name, null); } /** * Get named option as short. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @see #getShort(FileSystemOptions, String, Short) * @throws NumberFormatException if option value is not a valid short * * @since 2.0 */ protected short getShort(final FileSystemOptions opts, final String name, final short defaultValue) { return getShort(opts, name, Short.valueOf(defaultValue)).shortValue(); } /** * Get named option as short. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * @throws NumberFormatException if option value is not a valid short * * @since 2.0 */ protected Short getShort(final FileSystemOptions opts, final String name, final Short defaultValue) { Short value = (Short) getParam(opts, name); if (value == null) { final String str = getProperty(name); if (str == null) { return defaultValue; } value = Short.valueOf(str); } return value; } /** * Get named option as String. * * @param opts file system options to work with * @param name the option name * @return the option in {@code opts} or system properties, otherwise null * @see #getString(FileSystemOptions, String, String) * * @since 2.0 */ protected String getString(final FileSystemOptions opts, final String name) { return getString(opts, name, null); } /** * Get named option as String. * * @param opts file system options to work with * @param name the option name * @param defaultValue value to return if option is not present * @return the option in {@code opts} or system properties, otherwise {@code defaultValue} * * @since 2.0 */ protected String getString(final FileSystemOptions opts, final String name, final String defaultValue) { String value = (String) getParam(opts, name); if (value == null) { value = getProperty(name); if (value == null) { return defaultValue; } } return value; } /** * Get the target of this configuration. * * @return the specific file system class * * @since 1.0 */ protected abstract Class<? extends FileSystem> getConfigClass(); /** * Converts the given name into a System property key. * * @param name a name to combine with the builder prefix * @return name of system property * * @since 2.1 */ private String toPropertyKey(final String name) { return this.prefix + name; } /** * Get the system property for the given name. * * @param name The name to lookup combined with the prefix. * @return a system property or null * * @since 2.1 */ private String getProperty(final String name) { return System.getProperty(toPropertyKey(name)); } }