Build Integration

/**
 * Ant task to generate Java interface and classes for a protocol.
 * Extends ProtocolTask to inherit common functionality.
 */
public class SchemaTask extends ProtocolTask {
    
    /**
     * Command-line interface for schema compilation
     * @param args Command line arguments: <schema.avsc>... <output-folder>
     * @throws IOException if compilation fails
     */
    public static void main(String[] args) throws IOException;
    
    /**
     * Compile schema file - overrides parent implementation
     * @param src Source schema file
     * @param dest Destination directory
     * @throws IOException if compilation fails
     */
    @Override
    protected void doCompile(File src, File dest) throws IOException;
}

/**
 * Ant task to generate Java interface and classes for a protocol.
 * Extends org.apache.tools.ant.Task.
 */
public class ProtocolTask extends Task {
    
    /** Set the schema/protocol file */
    public void setFile(File file);
    
    /** Set the output directory */
    public void setDestdir(File dir);
    
    /** Set string type for generated classes (CharSequence, String, Utf8) */
    public void setStringType(GenericData.StringType stringType);
    
    /** Add fileset for batch processing */
    public void addFileSet(FileSet set);
    
    /** Execute the ant task */
    @Override
    public void execute() throws BuildException;
    
    /**
     * Compile protocol file - can be overridden by subclasses
     * @param src Source protocol file
     * @param dest Destination directory
     * @throws IOException if compilation fails
     */
    protected void doCompile(File src, File dest) throws IOException;
}

/**
 * Set string type for generated classes
 * @param stringType String representation type
 * Options: CharSequence (default), String, Utf8
 */
public void setStringType(GenericData.StringType stringType);

/** Get current string type setting */
public GenericData.StringType getStringType();

<!-- Load Avro compiler tasks -->
<taskdef name="schema" classname="org.apache.avro.compiler.specific.SchemaTask"
         classpath="path/to/avro-compiler.jar"/>
         
<taskdef name="protocol" classname="org.apache.avro.compiler.specific.ProtocolTask"
         classpath="path/to/avro-compiler.jar"/>

<!-- Compile single schema -->
<target name="compile-schema">
    <schema file="src/main/avro/User.avsc" 
            destdir="src/main/java"/>
</target>

<!-- Compile single protocol -->
<target name="compile-protocol">
    <protocol file="src/main/avro/EmailService.avpr" 
              destdir="src/main/java"/>
</target>

<!-- Compile all schemas in a directory -->
<target name="compile-all-schemas">
    <schema destdir="src/main/java">
        <fileset dir="src/main/avro">
            <include name="**/*.avsc"/>
        </fileset>
    </schema>
</target>

<!-- Compile all protocols in a directory -->
<target name="compile-all-protocols">
    <protocol destdir="src/main/java">
        <fileset dir="src/main/avro">
            <include name="**/*.avpr"/>
        </fileset>
    </protocol>
</target>

<!-- Configure string type -->
<target name="compile-with-string-type">
    <schema destdir="src/main/java" stringType="String">
        <fileset dir="src/main/avro">
            <include name="**/*.avsc"/>
        </fileset>
    </schema>
</target>

<!-- Complex build with dependencies -->
<target name="generate-avro-classes" depends="clean">
    <mkdir dir="src/main/java"/>
    
    <!-- Compile schemas first -->
    <schema destdir="src/main/java">
        <fileset dir="src/main/avro/schemas">
            <include name="**/*.avsc"/>
        </fileset>
    </schema>
    
    <!-- Then compile protocols that depend on schemas -->
    <protocol destdir="src/main/java">
        <fileset dir="src/main/avro/protocols">
            <include name="**/*.avpr"/>
        </fileset>
    </protocol>
</target>

# Schema compilation
java -cp avro-compiler.jar org.apache.avro.compiler.specific.SchemaTask \
     user.avsc order.avsc product.avsc src/main/java

# The last argument is the output directory
# All preceding arguments are schema files to compile

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-antrun-plugin</artifactId>
    <version>3.1.0</version>
    <executions>
        <execution>
            <phase>generate-sources</phase>
            <goals>
                <goal>run</goal>
            </goals>
            <configuration>
                <target>
                    <taskdef name="schema" 
                             classname="org.apache.avro.compiler.specific.SchemaTask"
                             classpathref="maven.compile.classpath"/>
                    
                    <schema destdir="${project.build.directory}/generated-sources/avro">
                        <fileset dir="src/main/avro">
                            <include name="**/*.avsc"/>
                        </fileset>
                    </schema>
                </target>
            </configuration>
        </execution>
    </executions>
    <dependencies>
        <dependency>
            <groupId>org.apache.avro</groupId>
            <artifactId>avro-compiler</artifactId>
            <version>1.12.0</version>
        </dependency>
    </dependencies>
</plugin>

try {
    ProtocolTask task = new ProtocolTask();
    task.setFile(new File("service.avpr"));
    task.setDestdir(new File("src/main/java"));
    task.execute();
} catch (BuildException e) {
    // Handle build failure
    System.err.println("Compilation failed: " + e.getMessage());
}

/** String type options for generated Java classes */
// From org.apache.avro.generic.GenericData
enum StringType {
    CharSequence,  // Default - generates CharSequence fields
    String,        // Generates String fields
    Utf8          // Generates Utf8 fields (Avro's internal string type)
}