[Demonstration 1]

[Buggy Method]
public static void build_constructor() {
    if (put_constructor) {
        buffer.append("public ").append(global_object.class_type).append("()\n\t{\n\t\t\n\t}");
    }
}

[Buggy Hunk]
buffer.append("public ").append(global_object.class_type).append("()\n\t{\n\t\t\n\t}");

[Patch]
buffer.append("public ").append(global_object.name).append("()\n\t{\n\t\t\n\t}");

[Demonstration 2]

[Buggy Method]
private static MethodSpec getConstructor(String dalName, List<String> primaryKey) {
    MethodSpec.Builder builder = MethodSpec.constructorBuilder().addModifiers(Modifier.PUBLIC).addParameter(ClassName.get(MetaData.instance.getDalNamespace(), dalName), "storage").addStatement("this.storage = $L", "storage").addCode("$L = new $T[]", PRIMARY_KEY_FIELD, String.class).beginControlFlow("");
    boolean first = true;
    for (String key : primaryKey) {
        if (first) {
            builder.addCode("$S", key);
            first = false;
        } else {
            builder.addCode(",\n$S", key);
        }
    }
    builder.addCode("\n");
    builder.endControlFlow("");
    return builder.build();
}

[Buggy Hunk]
.addParameter(ClassName.get(MetaData.instance.getDalNamespace(), dalName), "storage")

[Patch]
.addParameter(ClassName.get(MetaData.instance.getDalNamespace(), dalName), "storage", Modifier.FINAL)

[Demonstration 3]

[Buggy Method]
public static Result service(String ownerName, String projectName, String service, boolean isAdvertise) throws IOException, UnsupportedOperationException, ServletException {
    if (!isSupportedService(service)) {
        return forbidden(String.format("Unsupported service: '%s'", service));
    }
    Project project = Project.findByOwnerAndProjectName(ownerName, projectName);
    if (project == null) {
        return notFound();
    }
    models.User user = UserApp.currentUser();
    if (!isAllowed(project, service)) {
        if (user.isAnonymous()) {
            return BasicAuthAction.unauthorized(response());
        } else {
            // If you want the Git client showing your custom message to
            // the user, the Content-Type should be exact "text/plain"
            // without any parameter. For more details, see the code at
            // https://github.com/git/git/commit/426e70d4a11ce3b4f70636d57c6a0ab16ae08a00#diff-eea0ad565ec5903a11b6023755d491cfR154
            response().setHeader("Content-Type", "text/plain");
            return forbidden(String.format("'%s' has no permission to '%s/%s'.", user.name, ownerName, projectName));
        }
    }
    if (isAdvertise) {
        return ok(RepositoryService.gitAdvertise(project, service, response()));
    } else {
        if (request().body().isMaxSizeExceeded()) {
            return status(REQUEST_ENTITY_TOO_LARGE);
        } else {
            user.visits(project);
            return ok(RepositoryService.gitRpc(project, service, request(), response()));
        }
    }
}

[Buggy Hunk]
user.name, ownerName, projectName));

[Patch]
user.loginId, ownerName, projectName));