Issue #0 refine jdt2jar packaging

Agent-Logs-Url: https://github.com/simbo1905/java.util.json.Java21/sessions/46541410-0395-47ca-bf41-41ba6d0a8dc6

Co-authored-by: simbo1905 <322608+simbo1905@users.noreply.github.com>

Author: Copilot

jdt2jar/src/main/java/json/java21/jdt2jar/Jdt2Jar.java

@@ -5,7 +5,6 @@
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
-import java.io.InputStream;
 import java.io.UncheckedIOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
@@ -63,15 +62,15 @@ int execute(String[] args) throws IOException {
 
     final var schemaJson = Files.readString(options.schemaPath());
     final var schema = Json.parse(schemaJson);
-    final var generated = JtdCodegen.compileWithStats(schema, options.packageName(), options.className());
+    final var generatedBytes = JtdCodegen.compileBytes(schema, options.packageName(), options.className());
 
     if (options.runtime() != DEFAULT_RUNTIME) {
       throw new UsageException("Unsupported runtime version: " + options.runtime()
           + " (only 21 is currently emitted)");
     }
 
     final var output = options.output() != null ? options.output() : defaultOutput(options.schemaPath());
-    writeValidatorJar(output, options, schemaJson, generated.classBytes());
+    writeValidatorJar(output, options, schemaJson, generatedBytes);
 
     if (options.includeSources()) {
       writeSourceFile(sourcePathFor(output), options);
@@ -151,7 +150,7 @@ private static void copyJarEntries(JarOutputStream out, Set<String> written, Pat
           continue;
         }
         try (final var in = jar.getInputStream(entry)) {
-          writeEntry(out, written, name, readAllBytes(in));
+          writeEntry(out, written, name, in.readAllBytes());
         }
       }
     }
@@ -304,10 +303,6 @@ private static String toQualifiedName(String packageName, String className) {
     return packageName + "." + className;
   }
 
-  private static byte[] readAllBytes(InputStream in) throws IOException {
-    return in.readAllBytes();
-  }
-
   private static void printUsage() {
     System.out.println("""
         jdt2jar <schema.json> [options]

json-java21-jtd-codegen/src/main/java/json/java21/jtd/codegen/JtdCodegen.java

@@ -22,43 +22,62 @@ public final class JtdCodegen {
 
   static final Logger LOG = Logger.getLogger(JtdCodegen.class.getName());
   private static final AtomicLong COUNTER = new AtomicLong();
+  private static final String DEFAULT_PACKAGE = "json.java21.jtd.codegen";
 
   private JtdCodegen() {}
 
   /// Result of compilation including the validator and generated class statistics.
-    public record CompileResult(JtdValidator validator, int classfileBytes, byte[] classBytes) {}
+  public record CompileResult(JtdValidator validator, int classfileBytes, byte[] classBytes) {}
 
-    /// Public factory invoked by [JtdValidator.compileGenerated] via reflection.
-    public static JtdValidator compile(JsonValue schema) {
-        return compileWithStats(schema).validator();
-    }
+  /// Public factory invoked by [JtdValidator.compileGenerated] via reflection.
+  public static JtdValidator compile(JsonValue schema) {
+    return compileWithStats(schema).validator();
+  }
 
-    /// Compiles the schema and returns both the validator and the generated
-    /// classfile size in bytes. Useful for benchmarking and diagnostics.
-    public static CompileResult compileWithStats(JsonValue schema) {
-        return compileWithStats(schema, "json.java21.jtd.codegen", "Generated_" + COUNTER.incrementAndGet());
-    }
+  /// Compiles the schema and returns both the validator and the generated
+  /// classfile size in bytes. Useful for benchmarking and diagnostics.
+  public static CompileResult compileWithStats(JsonValue schema) {
+    final var className = "Generated_" + COUNTER.incrementAndGet();
+    final var bytes = buildBytes(schema, DEFAULT_PACKAGE, className);
+    return instantiate(schema, bytes, DEFAULT_PACKAGE, className);
+  }
+
+  /// Compiles the schema into a named validator class and returns the raw bytes.
+  ///
+  /// @param schema the JTD schema as a parsed [JsonValue]
+  /// @param packageName Java package for the generated validator
+  /// @param className Generated validator class name
+  /// @return the generated class bytes
+  public static byte[] compileBytes(JsonValue schema, String packageName, String className) {
+    return buildBytes(schema, packageName, className).clone();
+  }
 
-    /// Compiles the schema into a named validator class.
-    ///
-    /// @param schema the JTD schema as a parsed [JsonValue]
-    /// @param packageName Java package for the generated validator
-    /// @param className Generated validator class name
-    /// @return the validator, classfile size, and generated bytes
-    public static CompileResult compileWithStats(JsonValue schema, String packageName, String className) {
-        final var jtd = new Jtd();
-        final var compiled = jtd.compileToSchema(schema);
-        final var schemaJson = schema.toString();
+  private static CompileResult instantiate(JsonValue schema, byte[] bytes, String packageName, String className) {
+    final var internalName = packageName.replace('.', '/') + "/" + className;
+    final var schemaJson = schema.toString();
+    try {
+      final var lookup = MethodHandles.lookup();
+      final var clazz = lookup.defineClass(bytes);
+      final var ctor = clazz.getConstructor(String.class);
+      final var validator = (JtdValidator) ctor.newInstance(schemaJson);
+      return new CompileResult(validator, bytes.length, bytes.clone());
+    } catch (Exception e) {
+      throw new RuntimeException("Failed to load generated validator: " + internalName, e);
+    }
+  }
 
-        final var internalName = packageName.replace('.', '/') + "/" + className;
-        final var classDesc = ClassDesc.ofInternalName(internalName);
+  private static byte[] buildBytes(JsonValue schema, String packageName, String className) {
+    final var jtd = new Jtd();
+    final var compiled = jtd.compileToSchema(schema);
+    final var internalName = packageName.replace('.', '/') + "/" + className;
+    final var classDesc = ClassDesc.ofInternalName(internalName);
 
-        LOG.fine(() -> "Generating validator class: " + internalName);
+    LOG.fine(() -> "Generating validator class: " + internalName);
 
-        final var bytes = ClassFile.of().build(classDesc, clb -> {
-            clb.withVersion(ClassFile.JAVA_21_VERSION, 0);
-            clb.withFlags(ClassFile.ACC_PUBLIC | ClassFile.ACC_FINAL);
-            clb.withSuperclass(Descriptors.CD_Object);
+    return ClassFile.of().build(classDesc, clb -> {
+      clb.withVersion(ClassFile.JAVA_21_VERSION, 0);
+      clb.withFlags(ClassFile.ACC_PUBLIC | ClassFile.ACC_FINAL);
+      clb.withSuperclass(Descriptors.CD_Object);
       clb.withInterfaceSymbols(Descriptors.CD_JtdValidator);
       clb.with(SourceFileAttribute.of("JtdCodegen"));
 
@@ -69,20 +88,5 @@ public static CompileResult compileWithStats(JsonValue schema, String packageNam
       EmitScaffold.emitToString(clb, classDesc);
       EmitScaffold.emitValidateMethod(clb, classDesc, compiled);
     });
-
-        final JtdValidator validator;
-        if ("json.java21.jtd.codegen".equals(packageName)) {
-            try {
-                final var lookup = MethodHandles.lookup();
-                final var clazz = lookup.defineClass(bytes);
-                final var ctor = clazz.getConstructor(String.class);
-                validator = (JtdValidator) ctor.newInstance(schemaJson);
-            } catch (Exception e) {
-                throw new RuntimeException("Failed to load generated validator: " + internalName, e);
-            }
-        } else {
-            validator = JtdValidator.compile(schema);
-        }
-        return new CompileResult(validator, bytes.length, bytes.clone());
-    }
+  }
 }