Mercurial > jdk8-mips64-public > langtools / file revision

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  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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  *

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  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

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 package javax.tools;

 import java.io.File;

 import java.io.Writer;

 import java.nio.charset.Charset;

 import java.util.Locale;

 import java.util.concurrent.Callable;

 import javax.annotation.processing.Processor;

 /**

  * Interface to invoke Java™ programming language compilers from

  * programs.

  *

  * <p>The compiler might generate diagnostics during compilation (for

  * example, error messages).  If a diagnostic listener is provided,

  * the diagnostics will be supplied to the listener.  If no listener

  * is provided, the diagnostics will be formatted in an unspecified

  * format and written to the default output, which is {@code

  * System.err} unless otherwise specified.  Even if a diagnostic

  * listener is supplied, some diagnostics might not fit in a {@code

  * Diagnostic} and will be written to the default output.

  *

  * <p>A compiler tool has an associated standard file manager, which

  * is the file manager that is native to the tool (or built-in).  The

  * standard file manager can be obtained by calling {@linkplain

  * #getStandardFileManager getStandardFileManager}.

  *

  * <p>A compiler tool must function with any file manager as long as

  * any additional requirements as detailed in the methods below are

  * met.  If no file manager is provided, the compiler tool will use a

  * standard file manager such as the one returned by {@linkplain

  * #getStandardFileManager getStandardFileManager}.

  *

  * <p>An instance implementing this interface must conform to

  * <cite>The Java&trade; Language Specification</cite>

  * and generate class files conforming to

  * <cite>The Java&trade; Virtual Machine Specification</cite>.

  * The versions of these

  * specifications are defined in the {@linkplain Tool} interface.

  *

  * Additionally, an instance of this interface supporting {@link

  * javax.lang.model.SourceVersion#RELEASE_6 SourceVersion.RELEASE_6}

  * or higher must also support {@linkplain javax.annotation.processing

  * annotation processing}.

  *

  * <p>The compiler relies on two services: {@linkplain

  * DiagnosticListener diagnostic listener} and {@linkplain

  * JavaFileManager file manager}.  Although most classes and

  * interfaces in this package defines an API for compilers (and

  * tools in general) the interfaces {@linkplain DiagnosticListener},

  * {@linkplain JavaFileManager}, {@linkplain FileObject}, and

  * {@linkplain JavaFileObject} are not intended to be used in

  * applications.  Instead these interfaces are intended to be

  * implemented and used to provide customized services for a

  * compiler and thus defines an SPI for compilers.

  *

  * <p>There are a number of classes and interfaces in this package

  * which are designed to ease the implementation of the SPI to

  * customize the behavior of a compiler:

  *

  * <dl>

  *   <dt>{@link StandardJavaFileManager}</dt>

  *   <dd>

  *

  *     Every compiler which implements this interface provides a

  *     standard file manager for operating on regular {@linkplain

  *     java.io.File files}.  The StandardJavaFileManager interface

  *     defines additional methods for creating file objects from

  *     regular files.

  *

  *     <p>The standard file manager serves two purposes:

  *

  *     <ul>

  *       <li>basic building block for customizing how a compiler reads

  *       and writes files</li>

  *       <li>sharing between multiple compilation tasks</li>

  *     </ul>

  *

  *     <p>Reusing a file manager can potentially reduce overhead of

  *     scanning the file system and reading jar files.  Although there

  *     might be no reduction in overhead, a standard file manager must

  *     work with multiple sequential compilations making the following

  *     example a recommended coding pattern:

  *

  *     <pre>

  *       File[] files1 = ... ; // input for first compilation task

  *       File[] files2 = ... ; // input for second compilation task

  *

  *       JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();

  *       StandardJavaFileManager fileManager = compiler.getStandardFileManager(null, null, null);

  *

  *       {@code Iterable<? extends JavaFileObject>} compilationUnits1 =

  *           fileManager.getJavaFileObjectsFromFiles({@linkplain java.util.Arrays#asList Arrays.asList}(files1));

  *       compiler.getTask(null, fileManager, null, null, null, compilationUnits1).call();

  *

  *       {@code Iterable<? extends JavaFileObject>} compilationUnits2 =

  *           fileManager.getJavaFileObjects(files2); // use alternative method

  *       // reuse the same file manager to allow caching of jar files

  *       compiler.getTask(null, fileManager, null, null, null, compilationUnits2).call();

  *

  *       fileManager.close();</pre>

  *

  *   </dd>

  *

  *   <dt>{@link DiagnosticCollector}</dt>

  *   <dd>

  *     Used to collect diagnostics in a list, for example:

  *     <pre>

  *       {@code Iterable<? extends JavaFileObject>} compilationUnits = ...;

  *       JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();

  *       {@code DiagnosticCollector<JavaFileObject> diagnostics = new DiagnosticCollector<JavaFileObject>();}

  *       StandardJavaFileManager fileManager = compiler.getStandardFileManager(diagnostics, null, null);

  *       compiler.getTask(null, fileManager, diagnostics, null, null, compilationUnits).call();

  *

  *       for ({@code Diagnostic<? extends JavaFileObject>} diagnostic : diagnostics.getDiagnostics())

  *           System.out.format("Error on line %d in %s%n",

  *                             diagnostic.getLineNumber(),

  *                             diagnostic.getSource().toUri());

  *

  *       fileManager.close();</pre>

  *   </dd>

  *

  *   <dt>

  *     {@link ForwardingJavaFileManager}, {@link ForwardingFileObject}, and

  *     {@link ForwardingJavaFileObject}

  *   </dt>

  *   <dd>

  *

  *     Subclassing is not available for overriding the behavior of a

  *     standard file manager as it is created by calling a method on a

  *     compiler, not by invoking a constructor.  Instead forwarding

  *     (or delegation) should be used.  These classes makes it easy to

  *     forward most calls to a given file manager or file object while

  *     allowing customizing behavior.  For example, consider how to

  *     log all calls to {@linkplain JavaFileManager#flush}:

  *

  *     <pre>

  *       final {@linkplain java.util.logging.Logger Logger} logger = ...;

  *       {@code Iterable<? extends JavaFileObject>} compilationUnits = ...;

  *       JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();

  *       StandardJavaFileManager stdFileManager = compiler.getStandardFileManager(null, null, null);

  *       JavaFileManager fileManager = new ForwardingJavaFileManager(stdFileManager) {

  *           public void flush() throws IOException {

  *               logger.entering(StandardJavaFileManager.class.getName(), "flush");

  *               super.flush();

  *               logger.exiting(StandardJavaFileManager.class.getName(), "flush");

  *           }

  *       };

  *       compiler.getTask(null, fileManager, null, null, null, compilationUnits).call();</pre>

  *   </dd>

  *

  *   <dt>{@link SimpleJavaFileObject}</dt>

  *   <dd>

  *

  *     This class provides a basic file object implementation which

  *     can be used as building block for creating file objects.  For

  *     example, here is how to define a file object which represent

  *     source code stored in a string:

  *

  *     <pre>

  *       /**

  *        * A file object used to represent source coming from a string.

  *        {@code *}/

  *       public class JavaSourceFromString extends SimpleJavaFileObject {

  *           /**

  *            * The source code of this "file".

  *            {@code *}/

  *           final String code;

  *

  *           /**

  *            * Constructs a new JavaSourceFromString.

  *            * {@code @}param name the name of the compilation unit represented by this file object

  *            * {@code @}param code the source code for the compilation unit represented by this file object

  *            {@code *}/

  *           JavaSourceFromString(String name, String code) {

  *               super({@linkplain java.net.URI#create URI.create}("string:///" + name.replace('.','/') + Kind.SOURCE.extension),

  *                     Kind.SOURCE);

  *               this.code = code;

  *           }

  *

  *           {@code @}Override

  *           public CharSequence getCharContent(boolean ignoreEncodingErrors) {

  *               return code;

  *           }

  *       }</pre>

  *   </dd>

  * </dl>

  *

  * @author Peter von der Ahé

  * @author Jonathan Gibbons

  * @see DiagnosticListener

  * @see Diagnostic

  * @see JavaFileManager

  * @since 1.6

  */

 public interface JavaCompiler extends Tool, OptionChecker {

     /**

      * Creates a future for a compilation task with the given

      * components and arguments.  The compilation might not have

      * completed as described in the CompilationTask interface.

      *

      * <p>If a file manager is provided, it must be able to handle all

      * locations defined in {@link StandardLocation}.

      *

      * <p>Note that annotation processing can process both the

      * compilation units of source code to be compiled, passed with

      * the {@code compilationUnits} parameter, as well as class

      * files, whose names are passed with the {@code classes}

      * parameter.

      *

      * @param out a Writer for additional output from the compiler;

      * use {@code System.err} if {@code null}

      * @param fileManager a file manager; if {@code null} use the

      * compiler's standard filemanager

      * @param diagnosticListener a diagnostic listener; if {@code

      * null} use the compiler's default method for reporting

      * diagnostics

      * @param options compiler options, {@code null} means no options

      * @param classes names of classes to be processed by annotation

      * processing, {@code null} means no class names

      * @param compilationUnits the compilation units to compile, {@code

      * null} means no compilation units

      * @return an object representing the compilation

      * @throws RuntimeException if an unrecoverable error

      * occurred in a user supplied component.  The

      * {@linkplain Throwable#getCause() cause} will be the error in

      * user code.

      * @throws IllegalArgumentException if any of the given

      * compilation units are of other kind than

      * {@linkplain JavaFileObject.Kind#SOURCE source}

      */

     CompilationTask getTask(Writer out,

                             JavaFileManager fileManager,

                             DiagnosticListener<? super JavaFileObject> diagnosticListener,

                             Iterable<String> options,

                             Iterable<String> classes,

                             Iterable<? extends JavaFileObject> compilationUnits);

     /**

      * Gets a new instance of the standard file manager implementation

      * for this tool.  The file manager will use the given diagnostic

      * listener for producing any non-fatal diagnostics.  Fatal errors

      * will be signaled with the appropriate exceptions.

      *

      * <p>The standard file manager will be automatically reopened if

      * it is accessed after calls to {@code flush} or {@code close}.

      * The standard file manager must be usable with other tools.

      *

      * @param diagnosticListener a diagnostic listener for non-fatal

      * diagnostics; if {@code null} use the compiler's default method

      * for reporting diagnostics

      * @param locale the locale to apply when formatting diagnostics;

      * {@code null} means the {@linkplain Locale#getDefault() default locale}.

      * @param charset the character set used for decoding bytes; if

      * {@code null} use the platform default

      * @return the standard file manager

      */

     StandardJavaFileManager getStandardFileManager(

         DiagnosticListener<? super JavaFileObject> diagnosticListener,

         Locale locale,

         Charset charset);

     /**

      * Interface representing a future for a compilation task.  The

      * compilation task has not yet started.  To start the task, call

      * the {@linkplain #call call} method.

      *

      * <p>Before calling the call method, additional aspects of the

      * task can be configured, for example, by calling the

      * {@linkplain #setProcessors setProcessors} method.

      */

     interface CompilationTask extends Callable<Boolean> {

         /**

          * Sets processors (for annotation processing).  This will

          * bypass the normal discovery mechanism.

          *

          * @param processors processors (for annotation processing)

          * @throws IllegalStateException if the task has started

          */

         void setProcessors(Iterable<? extends Processor> processors);

         /**

          * Set the locale to be applied when formatting diagnostics and

          * other localized data.

          *

          * @param locale the locale to apply; {@code null} means apply no

          * locale

          * @throws IllegalStateException if the task has started

          */

         void setLocale(Locale locale);

         /**

          * Performs this compilation task.  The compilation may only

          * be performed once.  Subsequent calls to this method throw

          * IllegalStateException.

          *

          * @return true if and only all the files compiled without errors;

          * false otherwise

          *

          * @throws RuntimeException if an unrecoverable error occurred

          * in a user-supplied component.  The

          * {@linkplain Throwable#getCause() cause} will be the error

          * in user code.

          * @throws IllegalStateException if called more than once

          */

         Boolean call();

     }

 }