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* Copyright (c) 2005, 2024, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* 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).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package javax.tools;
import java.io.*;
import java.net.URI;
import java.nio.CharBuffer;
import java.util.Objects;
import javax.lang.model.element.Modifier;
import javax.lang.model.element.NestingKind;
/**
* Provides simple implementations for most methods in JavaFileObject.
* This class is designed to be subclassed and used as a basis for
* JavaFileObject implementations. Subclasses can override the
* implementation and specification of any method of this class as
* long as the general contract of JavaFileObject is obeyed.
*
* @since 1.6
*/
public class SimpleJavaFileObject implements JavaFileObject {
/**
* A URI for this file object.
*/
protected final URI uri;
/**
* The kind of this file object.
*/
protected final Kind kind;
/**
* Construct a SimpleJavaFileObject of the given kind and with the
* given URI.
*
* @param uri the URI for this file object
* @param kind the kind of this file object
*/
protected SimpleJavaFileObject(URI uri, Kind kind) {
Objects.requireNonNull(uri);
Objects.requireNonNull(kind);
if (uri.getPath() == null)
throw new IllegalArgumentException("URI must have a path: " + uri);
this.uri = uri;
this.kind = kind;
}
@Override
public URI toUri() {
return uri;
}
@Override
public String getName() {
return toUri().getPath();
}
/**
* {@inheritDoc FileObject}
* @implSpec
* This implementation always throws {@linkplain
* UnsupportedOperationException}.
*/
@Override
public InputStream openInputStream() throws IOException {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc FileObject}
* @implSpec
* This implementation always throws {@linkplain
* UnsupportedOperationException}.
*/
@Override
public OutputStream openOutputStream() throws IOException {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc FileObject}
* @implSpec
* This implementation wraps the result of {@link #getCharContent}
* in a {@link Reader}.
*
* @param ignoreEncodingErrors {@inheritDoc}
* @return a Reader wrapping the result of getCharContent
* @throws IllegalStateException {@inheritDoc}
* @throws UnsupportedOperationException {@inheritDoc}
* @throws IOException {@inheritDoc}
*/
@Override
public Reader openReader(boolean ignoreEncodingErrors) throws IOException {
CharSequence charContent = getCharContent(ignoreEncodingErrors);
if (charContent == null)
throw new UnsupportedOperationException();
if (charContent instanceof CharBuffer buffer && buffer.hasArray()) {
return new CharArrayReader(buffer.array());
}
return new StringReader(charContent.toString());
}
/**
* {@inheritDoc FileObject}
* @implSpec
* This implementation always throws {@linkplain
* UnsupportedOperationException}.
*/
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {
throw new UnsupportedOperationException();
}
/**
* {@inheritDoc FileObject}
* @implSpec
* This implementation wraps the result of {@link
* #openOutputStream} in a {@link Writer}.
*
* @return a Writer wrapping the result of openOutputStream
* @throws IllegalStateException {@inheritDoc}
* @throws UnsupportedOperationException {@inheritDoc}
* @throws IOException {@inheritDoc}
*/
@Override
public Writer openWriter() throws IOException {
return new OutputStreamWriter(openOutputStream());
}
/**
* {@inheritDoc FileObject}
* @implSpec
* This implementation returns {@code 0L}.
*
* @return {@code 0L}
*/
@Override
public long getLastModified() {
return 0L;
}
/**
* {@inheritDoc FileObject}
* @implSpec
* This implementation does nothing.
*
* @return {@code false}
*/
@Override
public boolean delete() {
return false;
}
/**
* @return {@code this.kind}
*/
@Override
public Kind getKind() {
return kind;
}
/**
* {@inheritDoc JavaFileObject}
* @implSpec
* This implementation compares the path of its URI to the given
* simple name. This method returns true if the given kind is
* equal to the kind of this object, and if the path is equal to
* {@code simpleName + kind.extension} or if it ends with {@code
* "/" + simpleName + kind.extension}.
*
* This method calls {@link #getKind} and {@link #toUri} and
* does not access the fields {@link #uri} and {@link #kind}
* directly.
*/
@Override
public boolean isNameCompatible(String simpleName, Kind kind) {
String baseName = simpleName + kind.extension;
return kind.equals(getKind())
&& (baseName.equals(toUri().getPath())
|| toUri().getPath().endsWith("/" + baseName));
}
/**
* {@inheritDoc JavaFileObject}
* @implSpec
* This implementation returns {@code null}.
*/
@Override
public NestingKind getNestingKind() { return null; }
/**
* {@inheritDoc JavaFileObject}
* @implSpec
* This implementation returns {@code null}.
*/
@Override
public Modifier getAccessLevel() { return null; }
@Override
public String toString() {
return getClass().getName() + "[" + toUri() + "]";
}
/**
* Creates a {@link JavaFileObject} which represents the given source content.
*
*
The provided {@code uri} will be returned from {@link #toUri()}.
* The provided {@code content} will be returned from {@link #getCharContent(boolean)}.
* The {@link #getKind()} method will return {@link Kind#SOURCE}.
*
*
All other methods will behave as described in the documentation in this class,
* as if the constructor is called with {@code uri} and {@code Kind.SOURCE}.
*
*
This method can be, for example, used to compile an in-memory String
* to a set of classfile in a target directory:
* {@snippet lang="java":
* var code = """
* public class CompiledCode {}
* """;
* var compiler = ToolProvider.getSystemJavaCompiler();
* var targetDirectory = "...";
* var task = compiler.getTask(null,
* null,
* null,
* List.of("-d", targetDirectory),
* null,
* List.of(SimpleJavaFileObject.forSource(URI.create("CompiledCode.java"), code)));
* if (!task.call()) {
* throw new IllegalStateException("Compilation failed!");
* }
* }
*
* @param uri that should be used for the resulting {@code JavaFileObject}
* @param content the content of the {@code JavaFileObject}
* @return a {@code JavaFileObject} representing the given source content.
* @since 23
*/
public static JavaFileObject forSource(URI uri, String content) {
return new SimpleJavaFileObject(uri, Kind.SOURCE) {
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) {
return content;
}
};
}
}