Apache Fesod Fesod

FastExcel 1.3 → Apache Fesod Migration Skill

Background

FastExcel (cn.idev.excel:fastexcel:1.3.0) was donated to the Apache Software Foundation and reborn as Apache Fesod (Incubating). The latest stable release is 2.0.1-incubating.

Key facts that affect how this migration works:

• cn.idev.excel.FastExcel and cn.idev.excel.FastExcelFactory are renamed, but Fesod ships @Deprecated bridge subclasses at org.apache.fesod.sheet.FastExcel and org.apache.fesod.sheet.FastExcelFactory so existing call sites compile after a package-only swap.
• The only hard breaking change is the Java package prefix: any *.excel.* imports must move to *.sheet.*. In practice, both of these are common and must be handled:
  • cn.idev.excel.* → org.apache.fesod.sheet.*
  • org.apache.fesod.excel.* → org.apache.fesod.sheet.*
• The CGLIB naming tag changed from ByFastExcelCGLIB → ByFesodCGLIB. This only matters if the project inspects generated class names at runtime.
• All annotation names, method signatures, and processing logic are identical.

The official Fesod migration doc recommends a three-phase gradual approach; this skill implements all three phases in one pass, but each phase is clearly labelled so the developer can stop after Phase 1 or Phase 2 if needed.

Phase 1 — Dependency swap (REQUIRED, zero code changes)

This phase alone is sufficient to make the project compile and run on Fesod with deprecation warnings. It is always safe to stop here first and run tests.

1a. Maven — single-module project

In pom.xml, find the FastExcel dependency block:

<dependency>
    <groupId>cn.idev.excel</groupId>
    <artifactId>fastexcel</artifactId>
    <version>...</version>
</dependency>

Replace it with:

<dependency>
    <groupId>org.apache.fesod</groupId>
    <artifactId>fesod-sheet</artifactId>
    <version>2.0.1-incubating</version>
</dependency>

Also remove the FastExcel version property if it exists, e.g.:

<fastexcel.version>1.3.0</fastexcel.version>

1b. Gradle

In build.gradle (or build.gradle.kts), replace:

// Groovy DSL
implementation 'cn.idev.excel:fastexcel:1.3.0'

with:

implementation 'org.apache.fesod:fesod-sheet:2.0.1-incubating'

Kotlin DSL:

implementation("org.apache.fesod:fesod-sheet:2.0.1-incubating")

Phase 2 — Package import rename (REQUIRED for compilation)

After swapping the dependency, any import under *.excel.* can be unresolved. Apply the following substitutions to every .java file in the project.

Process the table top-to-bottom (most specific first) to avoid partial replacements.

2x. Scope guardrails (IMPORTANT)

To avoid accidental regressions, apply replacements only in migration-relevant code.

• ✅ Safe targets:
  • import ... lines under cn.idev.excel.* / org.apache.fesod.excel.*
  • static call sites such as FastExcel.read( / FastExcel.write( / FastExcelFactory.*(
• ❌ Do not bulk-replace whole files or whole repositories for FastExcel text.
• ❌ Do not modify business literals unless explicitly requested:
  • @ExcelProperty("...") labels
  • sheet names / file names / i18n text
  • controller response strings
• ❌ Do not rewrite comments/Javadoc as part of mechanical migration.

If you use scripted replacement, constrain the pattern to imports and call expressions, then review diffs before running tests.

2a0. Pre-migrated namespace cleanup (very common)

Some repositories are already partially migrated and use org.apache.fesod.excel.* while still depending on older artifacts. After moving to fesod-sheet, these imports must be rewritten to org.apache.fesod.sheet.*.

Apply this explicit replacement before the detailed mapping table:

Then continue with the specific import mappings below.

2a. Core entry classes

Note: After this phase, FastExcel.read(...) and FastExcelFactory.writerSheet(...) still compile — they resolve to the @Deprecated bridge classes in Fesod. Phase 3 replaces them with the canonical FesodSheet class.

2b. Read API

2c. Write API

2d. Write handlers

2e. Annotations

2f. Converters

2g. Enums

2h. Exceptions and metadata

2i. Wildcard catch-all (apply last)

After all specific replacements above, scan for any remaining wildcard imports:

Apply this only after all the specific rules above, as a safety net.

Phase 3 — Entry class rename (STRONGLY RECOMMENDED)

FastExcel and FastExcelFactory compile in Fesod but are @Deprecated and will be removed in a future release. Replace all call sites with FesodSheet.

3a. Import replacement

3b. Call site replacement — FastExcel

3c. Call site replacement — FastExcelFactory

FastExcel 1.3 shipped FastExcelFactory as a second entry class with an identical API surface. All of its static methods map directly to FesodSheet:

3d. Type reference rename

If FastExcel or FastExcelFactory appear as a type name (not a call site), rename those too:

• Variable type: FastExcel x = ... → FesodSheet x = ...
• Class literal: FastExcel.class → FesodSheet.class

ExcelWriter and ExcelReader are not renamed — they keep the same class name.

Phase 4 — CGLIB class name (conditional)

This phase only applies if the project contains code that inspects or asserts on generated CGLIB class names at runtime, for example in tests or serialisation logic.

Search all .java files for the string ByFastExcelCGLIB. If found, replace with ByFesodCGLIB.

In Fesod, the naming policy is defined in org.apache.fesod.sheet.util.BeanMapUtils.FesodSheetNamingPolicy and its getTag() returns "ByFesodCGLIB".

If no file references ByFastExcelCGLIB, skip this phase entirely.

Phase 5 — Encoding and text safety (RECOMMENDED)

This phase prevents encoding-related breakage on Windows locales (for example GBK terminals).

• Keep source files in UTF-8; do not run global "remove non-ASCII" replacements.
• If compilation reports unmappable characters, fix only the specific broken lines.
• Prefer preserving existing business-language strings (Chinese/English/etc.) unless the task explicitly asks to normalize or translate them.
• If a replacement tool introduces malformed characters (e.g. �?), revert those hunks and re-apply scoped replacements.

Verification

After completing the desired phases, confirm the following:

Must be true after Phase 2:

• No .java file contains import cn.idev.excel.
• No .java file contains import org.apache.fesod.excel.
• No pom.xml or build.gradle references cn.idev.excel

Must be true after Phase 3 (additional):

• No .java file calls FastExcel. or FastExcelFactory. as a static call site
• No .java file imports org.apache.fesod.sheet.FastExcel or org.apache.fesod.sheet.FastExcelFactory

Must be true after Phase 4 (if applicable):

• No .java file contains the string ByFastExcelCGLIB

Must be true after Phase 5 (recommended):

• No malformed replacement artifacts such as �? remain in source files
• No unintended changes in business literals (headers/sheet names/messages) unless requested
• No accidental rewrites in comments/Javadoc caused by mechanical replace

Run the project's existing test suite to confirm functional equivalence:

# Maven
mvn clean test

# Gradle
./gradlew clean test

If tests fail with runtime messages like Unresolved compilation problem, rerun with a clean build first (mvn clean test / ./gradlew clean test) to avoid stale compiled classes masking the real source-level error.

Migration summary output

After applying all changes, produce a table in this format:

## Migration Summary

| Phase | File | Changes |
|---|---|---|
| 1 | pom.xml | Replaced cn.idev.excel:fastexcel:1.3.0 with org.apache.fesod:fesod-sheet:2.0.1-incubating |
| 2 | src/.../Foo.java | N import statements updated (cn.idev.excel → org.apache.fesod.sheet) |
| 3 | src/.../Bar.java | M FastExcel./FastExcelFactory. call sites renamed to FesodSheet. |
| 4 | src/.../Baz.java | ByFastExcelCGLIB → ByFesodCGLIB (if applicable) |
| 5 | src/.../Qux.java | Encoding/literal safety check passed (no malformed artifacts / no unintended literal rewrites) |

Remaining cn.idev.excel references : 0 ✅
Remaining FastExcel. call sites    : 0 ✅  (or N ⚠️  if Phase 3 was skipped)
Remaining ByFastExcelCGLIB refs    : 0 ✅  (or skipped — not present)

Source: apache/fesod — distributed by TomeVault.