diff --git a/app/src/main/java/com/hippo/unifile/Contracts.java b/app/src/main/java/com/hippo/unifile/Contracts.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/Contracts.java
rename to app/src/main/java/com/hippo/unifile/Contracts.kt
diff --git a/app/src/main/java/com/hippo/unifile/DocumentsContractApi19.java b/app/src/main/java/com/hippo/unifile/DocumentsContractApi19.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/DocumentsContractApi19.java
rename to app/src/main/java/com/hippo/unifile/DocumentsContractApi19.kt
diff --git a/app/src/main/java/com/hippo/unifile/DocumentsContractApi21.java b/app/src/main/java/com/hippo/unifile/DocumentsContractApi21.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/DocumentsContractApi21.java
rename to app/src/main/java/com/hippo/unifile/DocumentsContractApi21.kt
diff --git a/app/src/main/java/com/hippo/unifile/FilenameFilter.java b/app/src/main/java/com/hippo/unifile/FilenameFilter.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/FilenameFilter.java
rename to app/src/main/java/com/hippo/unifile/FilenameFilter.kt
diff --git a/app/src/main/java/com/hippo/unifile/MediaContract.java b/app/src/main/java/com/hippo/unifile/MediaContract.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/MediaContract.java
rename to app/src/main/java/com/hippo/unifile/MediaContract.kt
diff --git a/app/src/main/java/com/hippo/unifile/MediaFile.java b/app/src/main/java/com/hippo/unifile/MediaFile.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/MediaFile.java
rename to app/src/main/java/com/hippo/unifile/MediaFile.kt
diff --git a/app/src/main/java/com/hippo/unifile/RawFile.java b/app/src/main/java/com/hippo/unifile/RawFile.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/RawFile.java
rename to app/src/main/java/com/hippo/unifile/RawFile.kt
diff --git a/app/src/main/java/com/hippo/unifile/SingleDocumentFile.java b/app/src/main/java/com/hippo/unifile/SingleDocumentFile.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/SingleDocumentFile.java
rename to app/src/main/java/com/hippo/unifile/SingleDocumentFile.kt
diff --git a/app/src/main/java/com/hippo/unifile/TreeDocumentFile.java b/app/src/main/java/com/hippo/unifile/TreeDocumentFile.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/TreeDocumentFile.java
rename to app/src/main/java/com/hippo/unifile/TreeDocumentFile.kt
diff --git a/app/src/main/java/com/hippo/unifile/UniFile.java b/app/src/main/java/com/hippo/unifile/UniFile.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/UniFile.java
rename to app/src/main/java/com/hippo/unifile/UniFile.kt
diff --git a/app/src/main/java/com/hippo/unifile/UriHandler.java b/app/src/main/java/com/hippo/unifile/UriHandler.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/UriHandler.java
rename to app/src/main/java/com/hippo/unifile/UriHandler.kt
diff --git a/app/src/main/java/com/hippo/unifile/Utils.java b/app/src/main/java/com/hippo/unifile/Utils.kt
similarity index 100%
rename from app/src/main/java/com/hippo/unifile/Utils.java
rename to app/src/main/java/com/hippo/unifile/Utils.kt