TransferPackageProvider

Background and Use Cases

During the upgrade process from older to newer versions of FanRuan Report, extensive code refactoring was performed, including many package moves. This causes templates from older versions to fail with "class not found" errors when running on a newer version server.

The TransferPackageProvider interface provides class name conversion: when reading the class attribute from cpt/frm files, it maps old class names to new ones.

For example, if a template contains <ExampleAttr class="com.fr.xxx.MyClass"/> and MyClass has been moved to com.fr.xxx.moved.MyClass, this interface can be used to perform the substitution automatically.

Beyond package migration compatibility, this interface can also intercept embedded report objects via class substitution in special cases to influence execution logic.

Interface Definition

package com.fr.stable.fun;

import com.fr.stable.fun.mark.Mutable;

/**
 * Class name converter for package migration compatibility
 *
 * Created by loy on 2017/1/18.
 */
public interface TransferPackageProvider extends Mutable {

    String XML_TAG = "TransferPackageProvider";

    int CURRENT_LEVEL = 1;

    /**
     * Whether the given class name should be converted by this transformer
     * @param oldClassName the old class name read from the file
     */
    boolean accept(String oldClassName);

    /**
     * Returns the new class name to use as a replacement
     * @param oldClassName the old class name read from the file
     */
    String transfer(String oldClassName);
}

Supported Versions

Plugin Registration

Add the following node in plugin.xml:

<extra-core>
    <TransferPackageProvider class="your class name"/>
</extra-core>

How It Works

The interface takes effect through two main code paths:

1. TableDataXmlUtils: Applies transformation during dataset object deserialization
2. GeneralXMLTools: Applies transformation when parsing XMLable objects via readXMLable() and readStringAsXMLable()

Special limitation: Not all class elements in cpt/frm files are covered by this interface — only elements read via GeneralXMLTools.readXMLable / readStringAsXMLable and template dataset objects are affected.

Useful Links

• Demo: demo-transfer-package-provider