Basic decoding of GVariant values (except for Variant).
Change-Id: I43e495a57c1f045b91ce01d89f2010f61b5fb8f5
diff --git a/.gitignore b/.gitignore
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--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+*~
+/.idea
+/target
diff --git a/.mvn/jvm.config b/.mvn/jvm.config
new file mode 100644
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--- /dev/null
+++ b/.mvn/jvm.config
@@ -0,0 +1 @@
+--add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED --add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED --add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED --add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED --add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
diff --git a/.mvn/maven.config b/.mvn/maven.config
new file mode 100644
index 0000000..f8d5e4d
--- /dev/null
+++ b/.mvn/maven.config
@@ -0,0 +1 @@
+-Drevision=0.1.0-SNAPSHOT
diff --git a/COPYING b/COPYING
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index 0000000..0a04128
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+covered work, you indicate your acceptance of this License to do so.
+
+ 10. Automatic Licensing of Downstream Recipients.
+
+ Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License. You are not responsible
+for enforcing compliance by third parties with this License.
+
+ An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations. If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+ You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License. For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+ 11. Patents.
+
+ A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based. The
+work thus licensed is called the contributor's "contributor version".
+
+ A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version. For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+ Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+ In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement). To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+ If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients. "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+ If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+ A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License. You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+ Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+ 12. No Surrender of Others' Freedom.
+
+ If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all. For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+ 13. Use with the GNU Affero General Public License.
+
+ Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work. The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+ 14. Revised Versions of this License.
+
+ The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time. Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+ Each version is given a distinguishing version number. If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation. If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+ If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+ Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+ 15. Disclaimer of Warranty.
+
+ THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+ 16. Limitation of Liability.
+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ <program> Copyright (C) <year> <name of author>
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
diff --git a/pom.xml b/pom.xml
new file mode 100644
index 0000000..874369e
--- /dev/null
+++ b/pom.xml
@@ -0,0 +1,262 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"
+ xmlns="http://maven.apache.org/POM/4.0.0"
+ xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+
+ <modelVersion>4.0.0</modelVersion>
+
+ <groupId>eu.mulk.jgvariant</groupId>
+ <version>0.1.0-SNAPSHOT</version>
+
+ <artifactId>jgvariant-core</artifactId>
+ <packaging>jar</packaging>
+
+ <name>JGVariant</name>
+ <url>https://gerrit.benkard.de/plugins/gitiles/jgvariant</url>
+
+ <description>
+ GVariant serialization and deserialization.
+ </description>
+
+ <licenses>
+ <license>
+ <name>GNU Lesser General Public License v3.0 or later</name>
+ <url>https://www.gnu.org/licenses/lgpl-3.0.html</url>
+ </license>
+ </licenses>
+
+ <developers>
+ <developer>
+ <name>Matthias Benkard</name>
+ <email>code@mulk.eu</email>
+ <organization>Matthias Benkard</organization>
+ <organizationUrl>https://matthias.benkard.de</organizationUrl>
+ </developer>
+ </developers>
+
+ <scm>
+ <connection>scm:git:https://gerrit.benkard.de/jgvariant</connection>
+ <developerConnection>scm:git:ssh://gerrit.benkard.de:29418/jgvariant</developerConnection>
+ <url>https://gerrit.benkard.de/plugins/gitiles/jgvariant</url>
+ </scm>
+
+ <properties>
+ <maven.compiler.parameters>true</maven.compiler.parameters>
+ <maven.compiler.release>17</maven.compiler.release>
+
+ <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+ <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+
+ <compiler-plugin.version>3.8.1</compiler-plugin.version>
+ <failsafe-plugin.version>${surefire-plugin.version}</failsafe-plugin.version>
+ <jar-plugin.version>3.2.0</jar-plugin.version>
+ <maven-gpg-plugin.version>1.5</maven-gpg-plugin.version>
+ <maven-javadoc-plugin.version>3.2.0</maven-javadoc-plugin.version>
+ <maven-source-plugin.version>2.2.1</maven-source-plugin.version>
+ <nexus-staging-plugin.version>1.6.8</nexus-staging-plugin.version>
+ <spotless-plugin.version>2.17.6</spotless-plugin.version>
+ <surefire-plugin.version>3.0.0-M5</surefire-plugin.version>
+
+ <errorprone.version>2.10.0</errorprone.version>
+ <google-java-format.version>1.13.0</google-java-format.version>
+ <jetbrains-annotations.version>20.1.0</jetbrains-annotations.version>
+ <junit-jupiter.version>5.8.1</junit-jupiter.version>
+ </properties>
+
+ <distributionManagement>
+ <snapshotRepository>
+ <id>ossrh</id>
+ <url>https://s01.oss.sonatype.org/content/repositories/snapshots</url>
+ </snapshotRepository>
+ </distributionManagement>
+
+ <dependencyManagement>
+ <dependencies>
+ <dependency>
+ <groupId>com.google.errorprone</groupId>
+ <artifactId>error_prone_annotations</artifactId>
+ <version>${errorprone.version}</version>
+ </dependency>
+ </dependencies>
+ </dependencyManagement>
+
+ <dependencies>
+ <!-- Annotations -->
+ <dependency>
+ <groupId>com.google.errorprone</groupId>
+ <artifactId>error_prone_annotations</artifactId>
+ <optional>true</optional>
+ </dependency>
+ <dependency>
+ <groupId>org.jetbrains</groupId>
+ <artifactId>annotations</artifactId>
+ <version>${jetbrains-annotations.version}</version>
+ <optional>true</optional>
+ </dependency>
+
+ <!-- Testing -->
+ <dependency>
+ <groupId>org.junit.jupiter</groupId>
+ <artifactId>junit-jupiter-engine</artifactId>
+ <version>${junit-jupiter.version}</version>
+ <scope>test</scope>
+ </dependency>
+ <dependency>
+ <groupId>org.junit.jupiter</groupId>
+ <artifactId>junit-jupiter-api</artifactId>
+ <version>${junit-jupiter.version}</version>
+ <scope>test</scope>
+ </dependency>
+ </dependencies>
+
+ <build>
+
+ <pluginManagement>
+
+ <plugins>
+
+ <plugin>
+ <artifactId>maven-surefire-plugin</artifactId>
+ <version>${surefire-plugin.version}</version>
+ </plugin>
+
+ <plugin>
+ <artifactId>maven-failsafe-plugin</artifactId>
+ <version>${failsafe-plugin.version}</version>
+ </plugin>
+
+ <plugin>
+ <artifactId>maven-compiler-plugin</artifactId>
+ <version>${compiler-plugin.version}</version>
+ <configuration>
+ <fork>true</fork>
+ <compilerArgs>
+ <arg>-XDcompilePolicy=simple</arg>
+ <arg>-Xplugin:ErrorProne</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.model=ALL-UNNAMED</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED</arg>
+ <arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED</arg>
+ <arg>-J--add-opens=jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED</arg>
+ <arg>-J--add-opens=jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED</arg>
+ </compilerArgs>
+ <annotationProcessorPaths>
+ <path>
+ <groupId>com.google.errorprone</groupId>
+ <artifactId>error_prone_core</artifactId>
+ <version>${errorprone.version}</version>
+ </path>
+ </annotationProcessorPaths>
+ </configuration>
+ </plugin>
+
+ <plugin>
+ <artifactId>maven-jar-plugin</artifactId>
+ <version>${jar-plugin.version}</version>
+ </plugin>
+
+ </plugins>
+
+ </pluginManagement>
+
+ <plugins>
+
+ <plugin>
+ <groupId>com.diffplug.spotless</groupId>
+ <artifactId>spotless-maven-plugin</artifactId>
+ <version>${spotless-plugin.version}</version>
+ <configuration>
+ <java>
+ <removeUnusedImports/>
+ <importOrder>
+ <order>java,javax,org,com,de,io,dagger,eu.mulk,</order>
+ </importOrder>
+ <googleJavaFormat>
+ <version>${google-java-format.version}</version>
+ <style>GOOGLE</style>
+ </googleJavaFormat>
+ </java>
+ </configuration>
+ </plugin>
+
+ <plugin>
+ <groupId>org.sonatype.plugins</groupId>
+ <artifactId>nexus-staging-maven-plugin</artifactId>
+ <version>${nexus-staging-plugin.version}</version>
+ <extensions>true</extensions>
+ <configuration>
+ <serverId>ossrh</serverId>
+ <nexusUrl>https://s01.oss.sonatype.org/</nexusUrl>
+ <autoReleaseAfterClose>true</autoReleaseAfterClose>
+ </configuration>
+ </plugin>
+
+ </plugins>
+ </build>
+
+ <profiles>
+
+ <profile>
+ <id>release</id>
+
+ <build>
+ <plugins>
+
+ <plugin>
+ <groupId>org.apache.maven.plugins</groupId>
+ <artifactId>maven-source-plugin</artifactId>
+ <version>${maven-source-plugin.version}</version>
+ <executions>
+ <execution>
+ <id>attach-sources</id>
+ <goals>
+ <goal>jar-no-fork</goal>
+ </goals>
+ </execution>
+ </executions>
+ </plugin>
+
+ <plugin>
+ <groupId>org.apache.maven.plugins</groupId>
+ <artifactId>maven-javadoc-plugin</artifactId>
+ <version>${maven-javadoc-plugin.version}</version>
+ <executions>
+ <execution>
+ <id>attach-javadocs</id>
+ <goals>
+ <goal>jar</goal>
+ </goals>
+ </execution>
+ </executions>
+ </plugin>
+
+ <plugin>
+ <groupId>org.apache.maven.plugins</groupId>
+ <artifactId>maven-gpg-plugin</artifactId>
+ <version>${maven-gpg-plugin.version}</version>
+ <configuration>
+ <keyname>code@mulk.eu</keyname>
+ </configuration>
+ <executions>
+ <execution>
+ <id>sign-artifacts</id>
+ <phase>verify</phase>
+ <goals>
+ <goal>sign</goal>
+ </goals>
+ </execution>
+ </executions>
+ </plugin>
+
+ </plugins>
+ </build>
+ </profile>
+
+ </profiles>
+
+</project>
diff --git a/src/main/java/eu/mulk/jgvariant/core/Decoder.java b/src/main/java/eu/mulk/jgvariant/core/Decoder.java
new file mode 100644
index 0000000..2ebd0af
--- /dev/null
+++ b/src/main/java/eu/mulk/jgvariant/core/Decoder.java
@@ -0,0 +1,418 @@
+package eu.mulk.jgvariant.core;
+
+import static java.nio.ByteOrder.LITTLE_ENDIAN;
+
+import eu.mulk.jgvariant.core.Value.Array;
+import eu.mulk.jgvariant.core.Value.Bool;
+import eu.mulk.jgvariant.core.Value.Float64;
+import eu.mulk.jgvariant.core.Value.Int16;
+import eu.mulk.jgvariant.core.Value.Int32;
+import eu.mulk.jgvariant.core.Value.Int64;
+import eu.mulk.jgvariant.core.Value.Int8;
+import eu.mulk.jgvariant.core.Value.Maybe;
+import eu.mulk.jgvariant.core.Value.Str;
+import eu.mulk.jgvariant.core.Value.Structure;
+import eu.mulk.jgvariant.core.Value.Variant;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.RecordComponent;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.charset.Charset;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Type class for decodable {@link Value} types.
+ *
+ * <p>Use the {@code of*} family of constructor methods to acquire a suitable {@link Decoder} for
+ * the type you wish to decode.
+ *
+ * @param <T> the type that the {@link Decoder} can decode.
+ */
+@SuppressWarnings("java:S1610")
+public abstract class Decoder<T extends Value> {
+
+ private Decoder() {}
+
+ /**
+ * @throws java.nio.BufferUnderflowException if the byte buffer is shorter than the requested
+ * data.
+ */
+ public abstract T decode(ByteBuffer byteSlice);
+
+ abstract byte alignment();
+
+ @Nullable
+ abstract Integer fixedSize();
+
+ final boolean hasFixedSize() {
+ return fixedSize() != null;
+ }
+
+ public Decoder<T> withByteOrder(ByteOrder byteOrder) {
+ var delegate = this;
+
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return delegate.alignment();
+ }
+
+ @Override
+ public @Nullable Integer fixedSize() {
+ return delegate.fixedSize();
+ }
+
+ @Override
+ public T decode(ByteBuffer byteSlice) {
+ byteSlice.order(byteOrder);
+ return delegate.decode(byteSlice);
+ }
+ };
+ }
+
+ public static <U extends Value> Decoder<Array<U>> ofArray(Decoder<U> elementDecoder) {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return elementDecoder.alignment();
+ }
+
+ @Override
+ @Nullable
+ Integer fixedSize() {
+ return null;
+ }
+
+ @Override
+ public Array<U> decode(ByteBuffer byteSlice) {
+ List<U> elements;
+
+ var elementSize = elementDecoder.fixedSize();
+ if (elementSize != null) {
+ // A simple C-style array.
+ elements = new ArrayList<>(byteSlice.limit() / elementSize);
+ for (int i = 0; i < byteSlice.limit(); i += elementSize) {
+ var element = elementDecoder.decode(byteSlice.slice(i, elementSize));
+ elements.add(element);
+ }
+ } else {
+ // An array with aligned elements and a vector of framing offsets in the end.
+ int framingOffsetSize = byteCount(byteSlice.limit());
+ int lastFramingOffset =
+ getIntN(byteSlice.slice(byteSlice.limit() - framingOffsetSize, framingOffsetSize));
+ int elementCount = (byteSlice.limit() - lastFramingOffset) / framingOffsetSize;
+
+ elements = new ArrayList<>(elementCount);
+ int position = 0;
+ for (int i = 0; i < elementCount; i++) {
+ int framingOffset =
+ getIntN(
+ byteSlice.slice(lastFramingOffset + i * framingOffsetSize, framingOffsetSize));
+ elements.add(
+ elementDecoder.decode(byteSlice.slice(position, framingOffset - position)));
+ position = align(framingOffset, alignment());
+ }
+ }
+
+ return new Array<>(elements);
+ }
+ };
+ }
+
+ private static int align(int offset, byte alignment) {
+ return offset % alignment == 0 ? offset : offset + alignment - (offset % alignment);
+ }
+
+ private static int getIntN(ByteBuffer byteSlice) {
+ var intBytes = new byte[4];
+ byteSlice.get(intBytes, 0, Math.min(4, byteSlice.limit()));
+ return ByteBuffer.wrap(intBytes).order(LITTLE_ENDIAN).getInt();
+ }
+
+ @SuppressWarnings("java:S3358")
+ private static int byteCount(int n) {
+ return n < (1 << 8) ? 1 : n < (1 << 16) ? 2 : 4;
+ }
+
+ public static <U extends Value> Decoder<Maybe<U>> ofMaybe(Decoder<U> elementDecoder) {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return elementDecoder.alignment();
+ }
+
+ @Override
+ @Nullable
+ Integer fixedSize() {
+ return null;
+ }
+
+ @Override
+ public Maybe<U> decode(ByteBuffer byteSlice) {
+ if (!byteSlice.hasRemaining()) {
+ return new Maybe<>(Optional.empty());
+ } else {
+ if (!elementDecoder.hasFixedSize()) {
+ // Remove trailing zero byte.
+ byteSlice.limit(byteSlice.limit() - 1);
+ }
+
+ return new Maybe<>(Optional.of(elementDecoder.decode(byteSlice)));
+ }
+ }
+ };
+ }
+
+ @SafeVarargs
+ public static <U extends Record> Decoder<Structure<U>> ofStructure(
+ Class<U> recordType, Decoder<? extends Value>... componentDecoders) {
+ var recordComponents = recordType.getRecordComponents();
+ if (componentDecoders.length != recordComponents.length) {
+ throw new IllegalArgumentException(
+ "number of decoders (%d) does not match number of structure components (%d)"
+ .formatted(componentDecoders.length, recordComponents.length));
+ }
+
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return (byte) Arrays.stream(componentDecoders).mapToInt(Decoder::alignment).max().orElse(1);
+ }
+
+ @Override
+ public Integer fixedSize() {
+ int position = 0;
+ for (var componentDecoder : componentDecoders) {
+ var fixedComponentSize = componentDecoder.fixedSize();
+ if (fixedComponentSize == null) {
+ return null;
+ }
+
+ position = align(position, componentDecoder.alignment());
+ position += fixedComponentSize;
+ }
+
+ if (position == 0) {
+ return 1;
+ }
+
+ return align(position, alignment());
+ }
+
+ @Override
+ public Structure<U> decode(ByteBuffer byteSlice) {
+ int framingOffsetSize = byteCount(byteSlice.limit());
+
+ var recordConstructorArguments = new Object[recordComponents.length];
+
+ int position = 0;
+ int framingOffsetIndex = 0;
+ int componentIndex = 0;
+ for (var componentDecoder : componentDecoders) {
+ position = align(position, componentDecoder.alignment());
+
+ var fixedComponentSize = componentDecoder.fixedSize();
+ if (fixedComponentSize != null) {
+ recordConstructorArguments[componentIndex] =
+ componentDecoder.decode(byteSlice.slice(position, fixedComponentSize));
+ position += fixedComponentSize;
+ } else {
+ if (componentIndex == recordComponents.length - 1) {
+ // The last component never has a framing offset.
+ int endPosition = byteSlice.limit() - framingOffsetIndex * framingOffsetSize;
+ recordConstructorArguments[componentIndex] =
+ componentDecoder.decode(byteSlice.slice(position, endPosition - position));
+ position = endPosition;
+ } else {
+ int framingOffset =
+ getIntN(
+ byteSlice.slice(
+ byteSlice.limit() - (1 + framingOffsetIndex) * framingOffsetSize,
+ framingOffsetSize));
+ recordConstructorArguments[componentIndex] =
+ componentDecoder.decode(byteSlice.slice(position, framingOffset - position));
+ position = framingOffset;
+ ++framingOffsetIndex;
+ }
+ }
+
+ ++componentIndex;
+ }
+
+ try {
+ var recordComponentTypes =
+ Arrays.stream(recordType.getRecordComponents())
+ .map(RecordComponent::getType)
+ .toArray(Class<?>[]::new);
+ var recordConstructor = recordType.getDeclaredConstructor(recordComponentTypes);
+ return new Structure<>(recordConstructor.newInstance(recordConstructorArguments));
+ } catch (NoSuchMethodException
+ | InstantiationException
+ | IllegalAccessException
+ | InvocationTargetException e) {
+ throw new IllegalStateException(e);
+ }
+ }
+ };
+ }
+
+ public static Decoder<Variant> ofVariant() {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 8;
+ }
+
+ @Override
+ @Nullable
+ Integer fixedSize() {
+ return null;
+ }
+
+ @Override
+ public Variant decode(ByteBuffer byteSlice) {
+ // TODO
+ throw new UnsupportedOperationException("not implemented");
+ }
+ };
+ }
+
+ public static Decoder<Bool> ofBoolean() {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 1;
+ }
+
+ @Override
+ public Integer fixedSize() {
+ return 1;
+ }
+
+ @Override
+ public Bool decode(ByteBuffer byteSlice) {
+ return new Bool(byteSlice.get() != 0);
+ }
+ };
+ }
+
+ public static Decoder<Int8> ofInt8() {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 1;
+ }
+
+ @Override
+ public Integer fixedSize() {
+ return 1;
+ }
+
+ @Override
+ public Int8 decode(ByteBuffer byteSlice) {
+ return new Int8(byteSlice.get());
+ }
+ };
+ }
+
+ public static Decoder<Int16> ofInt16() {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 2;
+ }
+
+ @Override
+ public Integer fixedSize() {
+ return 2;
+ }
+
+ @Override
+ public Int16 decode(ByteBuffer byteSlice) {
+ return new Int16(byteSlice.getShort());
+ }
+ };
+ }
+
+ public static Decoder<Int32> ofInt32() {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 4;
+ }
+
+ @Override
+ public Integer fixedSize() {
+ return 4;
+ }
+
+ @Override
+ public Int32 decode(ByteBuffer byteSlice) {
+ return new Int32(byteSlice.getInt());
+ }
+ };
+ }
+
+ public static Decoder<Int64> ofInt64() {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 8;
+ }
+
+ @Override
+ public Integer fixedSize() {
+ return 8;
+ }
+
+ @Override
+ public Int64 decode(ByteBuffer byteSlice) {
+ return new Int64(byteSlice.getLong());
+ }
+ };
+ }
+
+ public static Decoder<Float64> ofFloat64() {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 8;
+ }
+
+ @Override
+ public Integer fixedSize() {
+ return 8;
+ }
+
+ @Override
+ public Float64 decode(ByteBuffer byteSlice) {
+ return new Float64(byteSlice.getDouble());
+ }
+ };
+ }
+
+ public static Decoder<Str> ofStr(Charset charset) {
+ return new Decoder<>() {
+ @Override
+ public byte alignment() {
+ return 1;
+ }
+
+ @Override
+ @Nullable
+ Integer fixedSize() {
+ return null;
+ }
+
+ @Override
+ public Str decode(ByteBuffer byteSlice) {
+ byteSlice.limit(byteSlice.limit() - 1);
+ return new Str(charset.decode(byteSlice).toString());
+ }
+ };
+ }
+}
diff --git a/src/main/java/eu/mulk/jgvariant/core/Value.java b/src/main/java/eu/mulk/jgvariant/core/Value.java
new file mode 100644
index 0000000..969f240
--- /dev/null
+++ b/src/main/java/eu/mulk/jgvariant/core/Value.java
@@ -0,0 +1,35 @@
+package eu.mulk.jgvariant.core;
+
+import java.util.List;
+import java.util.Optional;
+
+/** A value representable by the GVariant serialization format. */
+public sealed interface Value {
+
+ // Composite types
+ record Array<T extends Value>(List<T> values) implements Value {}
+
+ record Maybe<T extends Value>(Optional<T> value) implements Value {}
+
+ record Structure<T extends Record>(T values) implements Value {}
+
+ record Variant(Class<? extends Value> type, Value value) implements Value {}
+
+ // Primitive types
+ record Bool(boolean value) implements Value {
+ static Bool TRUE = new Bool(true);
+ static Bool FALSE = new Bool(false);
+ }
+
+ record Int8(byte value) implements Value {}
+
+ record Int16(short value) implements Value {}
+
+ record Int32(int value) implements Value {}
+
+ record Int64(long value) implements Value {}
+
+ record Float64(double value) implements Value {}
+
+ record Str(String value) implements Value {}
+}
diff --git a/src/main/java/module-info.java b/src/main/java/module-info.java
new file mode 100644
index 0000000..8880c0b
--- /dev/null
+++ b/src/main/java/module-info.java
@@ -0,0 +1,7 @@
+module eu.mulk.jgvariant.core {
+ requires java.base;
+ requires com.google.errorprone.annotations;
+ requires org.jetbrains.annotations;
+
+ exports eu.mulk.jgvariant.core;
+}
diff --git a/src/test/java/eu/mulk/jgvariant/core/DecoderTest.java b/src/test/java/eu/mulk/jgvariant/core/DecoderTest.java
new file mode 100644
index 0000000..4deb8bc
--- /dev/null
+++ b/src/test/java/eu/mulk/jgvariant/core/DecoderTest.java
@@ -0,0 +1,278 @@
+package eu.mulk.jgvariant.core;
+
+import static java.nio.ByteOrder.LITTLE_ENDIAN;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import eu.mulk.jgvariant.core.Value.Array;
+import eu.mulk.jgvariant.core.Value.Bool;
+import eu.mulk.jgvariant.core.Value.Int32;
+import eu.mulk.jgvariant.core.Value.Int8;
+import eu.mulk.jgvariant.core.Value.Maybe;
+import eu.mulk.jgvariant.core.Value.Str;
+import eu.mulk.jgvariant.core.Value.Structure;
+import java.nio.ByteBuffer;
+import java.util.List;
+import java.util.Optional;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Tests based on the examples given in <a
+ * href="https://people.gnome.org/~desrt/gvariant-serialisation.pdf">~desrt/gvariant-serialisation.pdf</a>.
+ */
+class DecoderTest {
+
+ @Test
+ void testString() {
+ var data = new byte[] {0x68, 0x65, 0x6C, 0x6C, 0x6F, 0x20, 0x77, 0x6F, 0x72, 0x6C, 0x64, 0x00};
+ var decoder = Decoder.ofStr(UTF_8);
+ assertEquals(new Str("hello world"), decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testMaybe() {
+ var data =
+ new byte[] {0x68, 0x65, 0x6C, 0x6C, 0x6F, 0x20, 0x77, 0x6F, 0x72, 0x6C, 0x64, 0x00, 0x00};
+ var decoder = Decoder.ofMaybe(Decoder.ofStr(UTF_8));
+ assertEquals(
+ new Maybe<>(Optional.of(new Str("hello world"))), decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testBooleanArray() {
+ var data = new byte[] {0x01, 0x00, 0x00, 0x01, 0x01};
+ var decoder = Decoder.ofArray(Decoder.ofBoolean());
+ assertEquals(
+ new Array<>(List.of(Bool.TRUE, Bool.FALSE, Bool.FALSE, Bool.TRUE, Bool.TRUE)),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testStructure() {
+ var data =
+ new byte[] {
+ 0x66, 0x6F, 0x6F, 0x00, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF, (byte) 0xFF, 0x04
+ };
+
+ record TestRecord(Str s, Int32 i) {}
+
+ var decoder = Decoder.ofStructure(TestRecord.class, Decoder.ofStr(UTF_8), Decoder.ofInt32());
+ assertEquals(
+ new Structure<>(new TestRecord(new Str("foo"), new Int32(-1))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testComplexStructureArray() {
+ var data =
+ new byte[] {
+ 0x68,
+ 0x69,
+ 0x00,
+ 0x00,
+ (byte) 0xfe,
+ (byte) 0xff,
+ (byte) 0xff,
+ (byte) 0xff,
+ 0x03,
+ 0x00,
+ 0x00,
+ 0x00,
+ 0x62,
+ 0x79,
+ 0x65,
+ 0x00,
+ (byte) 0xff,
+ (byte) 0xff,
+ (byte) 0xff,
+ (byte) 0xff,
+ 0x04,
+ 0x09,
+ 0x15
+ };
+
+ record TestRecord(Str s, Int32 i) {}
+
+ var decoder =
+ Decoder.ofArray(
+ Decoder.ofStructure(
+ TestRecord.class,
+ Decoder.ofStr(UTF_8),
+ Decoder.ofInt32().withByteOrder(LITTLE_ENDIAN)));
+ assertEquals(
+ new Array<>(
+ List.of(
+ new Structure<>(new TestRecord(new Str("hi"), new Int32(-2))),
+ new Structure<>(new TestRecord(new Str("bye"), new Int32(-1))))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testStringArray() {
+ var data =
+ new byte[] {
+ 0x69, 0x00, 0x63, 0x61, 0x6E, 0x00, 0x68, 0x61, 0x73, 0x00, 0x73, 0x74, 0x72, 0x69, 0x6E,
+ 0x67, 0x73, 0x3F, 0x00, 0x02, 0x06, 0x0a, 0x13
+ };
+ var decoder = Decoder.ofArray(Decoder.ofStr(UTF_8));
+ assertEquals(
+ new Array<>(List.of(new Str("i"), new Str("can"), new Str("has"), new Str("strings?"))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testNestedStructure() {
+ var data =
+ new byte[] {
+ 0x69, 0x63, 0x61, 0x6E, 0x00, 0x68, 0x61, 0x73, 0x00, 0x73, 0x74, 0x72, 0x69, 0x6E, 0x67,
+ 0x73, 0x3F, 0x00, 0x04, 0x0d, 0x05
+ };
+
+ record TestChild(Int8 b, Str s) {}
+ record TestParent(Structure<TestChild> tc, Array<Str> as) {}
+
+ var decoder =
+ Decoder.ofStructure(
+ TestParent.class,
+ Decoder.ofStructure(TestChild.class, Decoder.ofInt8(), Decoder.ofStr(UTF_8)),
+ Decoder.ofArray(Decoder.ofStr(UTF_8)));
+
+ assertEquals(
+ new Structure<>(
+ new TestParent(
+ new Structure<>(new TestChild(new Int8((byte) 0x69), new Str("can"))),
+ new Array<>(List.of(new Str("has"), new Str("strings?"))))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testSimpleStructure() {
+ var data = new byte[] {0x60, 0x70};
+
+ record TestRecord(Int8 b1, Int8 b2) {}
+
+ var decoder =
+ Decoder.ofStructure(
+ TestRecord.class,
+ Decoder.ofInt8().withByteOrder(LITTLE_ENDIAN),
+ Decoder.ofInt8().withByteOrder(LITTLE_ENDIAN));
+
+ assertEquals(
+ new Structure<>(new TestRecord(new Int8((byte) 0x60), new Int8((byte) 0x70))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testPaddedStructureRight() {
+ var data = new byte[] {0x60, 0x00, 0x00, 0x00, 0x70, 0x00, 0x00, 0x00};
+
+ record TestRecord(Int32 b1, Int8 b2) {}
+
+ var decoder =
+ Decoder.ofStructure(
+ TestRecord.class,
+ Decoder.ofInt32().withByteOrder(LITTLE_ENDIAN),
+ Decoder.ofInt8().withByteOrder(LITTLE_ENDIAN));
+
+ assertEquals(
+ new Structure<>(new TestRecord(new Int32(0x60), new Int8((byte) 0x70))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testPaddedStructureLeft() {
+ var data = new byte[] {0x60, 0x00, 0x00, 0x00, 0x70, 0x00, 0x00, 0x00};
+
+ record TestRecord(Int8 b1, Int32 b2) {}
+
+ var decoder =
+ Decoder.ofStructure(
+ TestRecord.class,
+ Decoder.ofInt8().withByteOrder(LITTLE_ENDIAN),
+ Decoder.ofInt32().withByteOrder(LITTLE_ENDIAN));
+
+ assertEquals(
+ new Structure<>(new TestRecord(new Int8((byte) 0x60), new Int32(0x70))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testSimpleStructureArray() {
+ var data =
+ new byte[] {
+ 0x60,
+ 0x00,
+ 0x00,
+ 0x00,
+ 0x70,
+ 0x00,
+ 0x00,
+ 0x00,
+ (byte) 0x88,
+ 0x02,
+ 0x00,
+ 0x00,
+ (byte) 0xF7,
+ 0x00,
+ 0x00,
+ 0x00
+ };
+
+ record TestRecord(Int32 b1, Int8 b2) {}
+
+ var decoder =
+ Decoder.ofArray(
+ Decoder.ofStructure(
+ TestRecord.class,
+ Decoder.ofInt32().withByteOrder(LITTLE_ENDIAN),
+ Decoder.ofInt8().withByteOrder(LITTLE_ENDIAN)));
+
+ assertEquals(
+ new Array<>(
+ List.of(
+ new Structure<>(new TestRecord(new Int32(96), new Int8((byte) 0x70))),
+ new Structure<>(new TestRecord(new Int32(648), new Int8((byte) 0xf7))))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testByteArray() {
+ var data = new byte[] {0x04, 0x05, 0x06, 0x07};
+
+ var decoder = Decoder.ofArray(Decoder.ofInt8());
+
+ assertEquals(
+ new Array<>(
+ List.of(
+ new Int8((byte) 0x04),
+ new Int8((byte) 0x05),
+ new Int8((byte) 0x06),
+ new Int8((byte) 0x07))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testIntegerArray() {
+ var data = new byte[] {0x04, 0x00, 0x00, 0x00, 0x02, 0x01, 0x00, 0x00};
+
+ var decoder = Decoder.ofArray(Decoder.ofInt32().withByteOrder(LITTLE_ENDIAN));
+
+ assertEquals(
+ new Array<>(List.of(new Int32(4), new Int32(258))), decoder.decode(ByteBuffer.wrap(data)));
+ }
+
+ @Test
+ void testDictionaryEntry() {
+ var data =
+ new byte[] {0x61, 0x20, 0x6B, 0x65, 0x79, 0x00, 0x00, 0x00, 0x02, 0x02, 0x00, 0x00, 0x06};
+
+ record TestEntry(Str key, Int32 value) {}
+
+ var decoder =
+ Decoder.ofStructure(
+ TestEntry.class, Decoder.ofStr(UTF_8), Decoder.ofInt32().withByteOrder(LITTLE_ENDIAN));
+ assertEquals(
+ new Structure<>(new TestEntry(new Str("a key"), new Int32(514))),
+ decoder.decode(ByteBuffer.wrap(data)));
+ }
+}