1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/classes/javax/annotation/processing/Filer.java Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,261 @@
1.4 +/*
1.5 + * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Sun designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Sun in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.25 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.26 + * have any questions.
1.27 + */
1.28 +
1.29 +package javax.annotation.processing;
1.30 +
1.31 +import javax.tools.JavaFileManager;
1.32 +import javax.tools.*;
1.33 +import javax.lang.model.element.Element;
1.34 +import java.io.IOException;
1.35 +
1.36 +/**
1.37 + * This interface supports the creation of new files by an annotation
1.38 + * processor. Files created in this way will be known to the
1.39 + * annotation processing tool implementing this interface, better
1.40 + * enabling the tool to manage them. Source and class files so
1.41 + * created will be considered for processing by the tool after the
1.42 + * {@code close} method has been called on the {@code Writer} or
1.43 + * {@code OutputStream} used to write the contents of the file.
1.44 + *
1.45 + * Three kinds of files are distinguished: source files, class files,
1.46 + * and auxiliary resource files.
1.47 + *
1.48 + * <p> There are two distinguished supported locations (subtrees
1.49 + * within the logical file system) where newly created files are
1.50 + * placed: one for {@linkplain
1.51 + * javax.tools.StandardLocation#SOURCE_OUTPUT new source files}, and
1.52 + * one for {@linkplain javax.tools.StandardLocation#CLASS_OUTPUT new
1.53 + * class files}. (These might be specified on a tool's command line,
1.54 + * for example, using flags such as {@code -s} and {@code -d}.) The
1.55 + * actual locations for new source files and new class files may or
1.56 + * may not be distinct on a particular run of the tool. Resource
1.57 + * files may be created in either location. The methods for reading
1.58 + * and writing resources take a relative name argument. A relative
1.59 + * name is a non-null, non-empty sequence of path segments separated
1.60 + * by {@code '/'}; {@code '.'} and {@code '..'} are invalid path
1.61 + * segments. A valid relative name must match the
1.62 + * "path-rootless" rule of <a
1.63 + * href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986</a>, section
1.64 + * 3.3.
1.65 + *
1.66 + * <p>The file creation methods take a variable number of arguments to
1.67 + * allow the <em>originating elements</em> to be provided as hints to
1.68 + * the tool infrastructure to better manage dependencies. The
1.69 + * originating elements are the types or packages (representing {@code
1.70 + * package-info} files) which caused an annotation processor to
1.71 + * attempt to create a new file. For example, if an annotation
1.72 + * processor tries to create a source file, {@code
1.73 + * GeneratedFromUserSource}, in response to processing
1.74 + *
1.75 + * <blockquote><pre>
1.76 + * @Generate
1.77 + * public class UserSource {}
1.78 + * </pre></blockquote>
1.79 + *
1.80 + * the type element for {@code UserSource} should be passed as part of
1.81 + * the creation method call as in:
1.82 + *
1.83 + * <blockquote><pre>
1.84 + * filer.createSourceFile("GeneratedFromUserSource",
1.85 + * eltUtils.getTypeElement("UserSource"));
1.86 + * </pre></blockquote>
1.87 + *
1.88 + * If there are no originating elements, none need to be passed. This
1.89 + * information may be used in an incremental environment to determine
1.90 + * the need to rerun processors or remove generated files.
1.91 + * Non-incremental environments may ignore the originating element
1.92 + * information.
1.93 + *
1.94 + * <p> During each run of an annotation processing tool, a file with a
1.95 + * given pathname may be created only once. If that file already
1.96 + * exists before the first attempt to create it, the old contents will
1.97 + * be deleted. Any subsequent attempt to create the same file during
1.98 + * a run will throw a {@link FilerException}, as will attempting to
1.99 + * create both a class file and source file for the same type name or
1.100 + * same package name. The {@linkplain Processor initial inputs} to
1.101 + * the tool are considered to be created by the zeroth round;
1.102 + * therefore, attempting to create a source or class file
1.103 + * corresponding to one of those inputs will result in a {@link
1.104 + * FilerException}.
1.105 + *
1.106 + * <p> In general, processors must not knowingly attempt to overwrite
1.107 + * existing files that were not generated by some processor. A {@code
1.108 + * Filer} may reject attempts to open a file corresponding to an
1.109 + * existing type, like {@code java.lang.Object}. Likewise, the
1.110 + * invoker of the annotation processing tool must not knowingly
1.111 + * configure the tool such that the discovered processors will attempt
1.112 + * to overwrite existing files that were not generated.
1.113 + *
1.114 + * <p> Processors can indicate a source or class file is generated by
1.115 + * including an {@link javax.annotation.Generated @Generated}
1.116 + * annotation.
1.117 + *
1.118 + * <p> Note that some of the effect of overwriting a file can be
1.119 + * achieved by using a <i>decorator</i>-style pattern. Instead of
1.120 + * modifying a class directly, the class is designed so that either
1.121 + * its superclass is generated by annotation processing or subclasses
1.122 + * of the class are generated by annotation processing. If the
1.123 + * subclasses are generated, the parent class may be designed to use
1.124 + * factories instead of public constructors so that only subclass
1.125 + * instances would be presented to clients of the parent class.
1.126 + *
1.127 + * @author Joseph D. Darcy
1.128 + * @author Scott Seligman
1.129 + * @author Peter von der Ahé
1.130 + * @since 1.6
1.131 + */
1.132 +public interface Filer {
1.133 + /**
1.134 + * Creates a new source file and returns an object to allow
1.135 + * writing to it. The file's name and path (relative to the
1.136 + * {@linkplain StandardLocation#SOURCE_OUTPUT root output location
1.137 + * for source files}) are based on the type to be declared in that
1.138 + * file. If more than one type is being declared, the name of the
1.139 + * principal top-level type (the public one, for example) should
1.140 + * be used. A source file can also be created to hold information
1.141 + * about a package, including package annotations. To create a
1.142 + * source file for a named package, have {@code name} be the
1.143 + * package's name followed by {@code ".package-info"}; to create a
1.144 + * source file for an unnamed package, use {@code "package-info"}.
1.145 + *
1.146 + * <p> Note that to use a particular {@linkplain
1.147 + * java.nio.charset.Charset charset} to encode the contents of the
1.148 + * file, an {@code OutputStreamWriter} with the chosen charset can
1.149 + * be created from the {@code OutputStream} from the returned
1.150 + * object. If the {@code Writer} from the returned object is
1.151 + * directly used for writing, its charset is determined by the
1.152 + * implementation. An annotation processing tool may have an
1.153 + * {@code -encoding} flag or analogous option for specifying this;
1.154 + * otherwise, it will typically be the platform's default
1.155 + * encoding.
1.156 + *
1.157 + * <p>To avoid subsequent errors, the contents of the source file
1.158 + * should be compatible with the {@linkplain
1.159 + * ProcessingEnvironment#getSourceVersion source version} being used
1.160 + * for this run.
1.161 + *
1.162 + * @param name canonical (fully qualified) name of the principal type
1.163 + * being declared in this file or a package name followed by
1.164 + * {@code ".package-info"} for a package information file
1.165 + * @param originatingElements type or package elements causally
1.166 + * associated with the creation of this file, may be elided or
1.167 + * {@code null}
1.168 + * @return a {@code JavaFileObject} to write the new source file
1.169 + * @throws FilerException if the same pathname has already been
1.170 + * created, the same type has already been created, or the name is
1.171 + * not valid for a type
1.172 + * @throws IOException if the file cannot be created
1.173 + */
1.174 + JavaFileObject createSourceFile(CharSequence name,
1.175 + Element... originatingElements) throws IOException;
1.176 +
1.177 + /**
1.178 + * Creates a new class file, and returns an object to allow
1.179 + * writing to it. The file's name and path (relative to the
1.180 + * {@linkplain StandardLocation#CLASS_OUTPUT root output location
1.181 + * for class files}) are based on the name of the type being
1.182 + * written. A class file can also be created to hold information
1.183 + * about a package, including package annotations. To create a
1.184 + * class file for a named package, have {@code name} be the
1.185 + * package's name followed by {@code ".package-info"}; creating a
1.186 + * class file for an unnamed package is not supported.
1.187 + *
1.188 + * <p>To avoid subsequent errors, the contents of the class file
1.189 + * should be compatible with the {@linkplain
1.190 + * ProcessingEnvironment#getSourceVersion source version} being used
1.191 + * for this run.
1.192 + *
1.193 + * @param name binary name of the type being written or a package name followed by
1.194 + * {@code ".package-info"} for a package information file
1.195 + * @param originatingElements type or package elements causally
1.196 + * associated with the creation of this file, may be elided or
1.197 + * {@code null}
1.198 + * @return a {@code JavaFileObject} to write the new class file
1.199 + * @throws FilerException if the same pathname has already been
1.200 + * created, the same type has already been created, or the name is
1.201 + * not valid for a type
1.202 + * @throws IOException if the file cannot be created
1.203 + */
1.204 + JavaFileObject createClassFile(CharSequence name,
1.205 + Element... originatingElements) throws IOException;
1.206 +
1.207 + /**
1.208 + * Creates a new auxiliary resource file for writing and returns a
1.209 + * file object for it. The file may be located along with the
1.210 + * newly created source files, newly created binary files, or
1.211 + * other supported location. The locations {@link
1.212 + * StandardLocation#CLASS_OUTPUT CLASS_OUTPUT} and {@link
1.213 + * StandardLocation#SOURCE_OUTPUT SOURCE_OUTPUT} must be
1.214 + * supported. The resource may be named relative to some package
1.215 + * (as are source and class files), and from there by a relative
1.216 + * pathname. In a loose sense, the full pathname of the new file
1.217 + * will be the concatenation of {@code location}, {@code pkg}, and
1.218 + * {@code relativeName}.
1.219 + *
1.220 + * <p>Files created via this method are not registered for
1.221 + * annotation processing, even if the full pathname of the file
1.222 + * would correspond to the full pathname of a new source file
1.223 + * or new class file.
1.224 + *
1.225 + * @param location location of the new file
1.226 + * @param pkg package relative to which the file should be named,
1.227 + * or the empty string if none
1.228 + * @param relativeName final pathname components of the file
1.229 + * @param originatingElements type or package elements causally
1.230 + * associated with the creation of this file, may be elided or
1.231 + * {@code null}
1.232 + * @return a {@code FileObject} to write the new resource
1.233 + * @throws IOException if the file cannot be created
1.234 + * @throws FilerException if the same pathname has already been
1.235 + * created
1.236 + * @throws IllegalArgumentException for an unsupported location
1.237 + * @throws IllegalArgumentException if {@code relativeName} is not relative
1.238 + */
1.239 + FileObject createResource(JavaFileManager.Location location,
1.240 + CharSequence pkg,
1.241 + CharSequence relativeName,
1.242 + Element... originatingElements) throws IOException;
1.243 +
1.244 + /**
1.245 + * Returns an object for reading an existing resource. The
1.246 + * locations {@link StandardLocation#CLASS_OUTPUT CLASS_OUTPUT}
1.247 + * and {@link StandardLocation#SOURCE_OUTPUT SOURCE_OUTPUT} must
1.248 + * be supported.
1.249 + *
1.250 + * @param location location of the file
1.251 + * @param pkg package relative to which the file should be searched,
1.252 + * or the empty string if none
1.253 + * @param relativeName final pathname components of the file
1.254 + * @return an object to read the file
1.255 + * @throws FilerException if the same pathname has already been
1.256 + * opened for writing
1.257 + * @throws IOException if the file cannot be opened
1.258 + * @throws IllegalArgumentException for an unsupported location
1.259 + * @throws IllegalArgumentException if {@code relativeName} is not relative
1.260 + */
1.261 + FileObject getResource(JavaFileManager.Location location,
1.262 + CharSequence pkg,
1.263 + CharSequence relativeName) throws IOException;
1.264 +}
