[HOW TO][Windows] Manually Deodex and Odex back


The purpose of this thread is to give basics to manually deodex and odexing back framework and apk files

Credits and Thanks to :



and many others I forgot

Theory :



In Android file system, applications and framework files come in packages with the extension .apk or .jar. These APKs or JARs contain certain .odex files whose supposed function is to save space. These ‘odex’ files are actually collections of parts of an application that are optimized before booting. Doing so speeds up the boot process, as it preloads part of an application. On the other hand, it also makes hacking those applications difficult because a part of the coding has already been extracted to another location before execution.


Deodexing is basically repackaging of these APKs or JARs in a certain way, such that the .odex files are reassembled into classes.dex files directly integrated inside the APKs or JARs. By doing that, all pieces of an application package are put together back in one place.
For now, we need Baksmali.jar and Smali.jar to deodex, it seems these tools are not perfect and it seems to be why deodexed stock browser is laging/freezing.
This is the reason why there is a return to odexed customROMs

Prerequisites :

You will need these files :


* backsmali.jar
* smali.jar
* custom java.awt.jar
* dexopt wrapper
* recent version of busybox

all included in the attached .zip (end of post)

You will also need :


* your GS2
* with the official odexed firmware you want to mod
* rooted and with root explorer (pay app but really usefull) and with CWM recovery (better )
* ADB installed and working in su (#)
* copy dexopt-wrapper in /system/bin/ and giving it 755 permissions (using root explorer or command: chmod 755 /system/bin/dexopt-wrapper
* optional (if errors during odexing back) overwrite installed busybox with the one included here in /system/xbin/

You have to know :
* even on stock firmware (odexed) there are some deodexed .apk (like framework-res.apk in /system/framework/ and like some .apk in system/app/)

Tip on Windows "Vista / 7" : open a CMD prompt in a specified folder


1. Select the folder you want to open in the command prompt
2. Right-click on it while holding the Shift key
3. Select Open command window here

Manually Deodexing :

theory :


to decompil an odex file you need Baksmali.jar and you needs the BOOTCLASSPATH
BOOTCLASSPATH is a list in specific order of some framework .jar files

** To decompil and re-odex back .odex from JAR file you need to use the BOOTCLASSPATH specified in the init.rc file located in the root folder of your GS2 : (open init.rc with notepad ++)

Extract of I9100 init.rc :
export BOOTCLASSPATH /system/framework/core.jar:/system/framework/bouncycastle.jar:/system/framework/ext.jar:/system/framework/framework.jar:/system/framework/android.policy.jar:/system/framework/services.jar:/system/framework/core-junit.jar

** To decompil an .odex from APK file, BOOTCLASSPATH is different in fonction of the APKs, so the lazy way is to include all the .JAR files of the framework folder
2 applications : Emails.apk and MobilePrint.apk needs one more custom java.awt.jar

1/ put in the same folder :


* apk to deodex
* all system/framework files
add :
* custom java.awt.jar
* baksami.jar
* smali.jar
* zipalign.exe

2/ open CMD prompt in this folder (see above for how to)

3/ Deodexing Framework file (I will take android.policy.jar for example) :

* BAKSMALI of the android.policy.odex :


java -Xmx1024m -jar baksmali.jar -c :core.jar:bouncycastle.jar:ext.jar:framework.jar:android.policy.jar:services.jar:core-junit.jar -x android.policy.odex
* This create an out folder. You can now modify some files (like adding Advanced power menu)

* SMALI the / out folder in a classes.dex file :


java -Xmx1024m -jar smali.jar out -o classes.dex
* finally deodex your android.policy.jar :


open android.policy.jar with 7zip without extracting
push the classes.dex created in the 7zip window in the root folder
close the 7zip windows and here is your deodexed android.policy.jar

4/ Deodexing APK in system/app (I will take SystemUI.apk for exemple) :

* BAKSMALI of the SystemUI.odex :


java -Xmx1024m -jar baksmali.jar -c -x SystemUI.odex
* an out folder is created. You can modify the files inside if you want.

* SMALI the / out folder in a classes.dex file :


java -Xmx1024m -jar smali.jar out -o classes.dex
* finally deodex your SystemUI.apk :


open SystemUI.apk with 7zip without extracting
push the classes.dex created in the 7zip window in the root folder
close the 7zip windows and here is your deodexed SystemUI.apk

* extra step for APKs : zipaplign of your new deodexed SystemUI.apk
--> In the same CMD prompt windows, type :


zipalign -v 4 SystemUI.apk zip_SystemUI.apk
A zip_SystemUI.apk file is created. Delete your deodexed SystemUI.apk and rename zip_SystemUI.apk in SystemUI.apk


the theory :


*You will need to copy the (custom) deodexed file (.jar or .apk) in the system/framework/ folder of your phone.
*You will use dexopt wrapper (already copied in your phone) to obtain a new .odex file (patched_android.policy.odex for example)
* You will copy the signature of original .odex file to patched.odex file - if not, the phone won't boot ...

How To :
1/ backup your original files (apk jar and odex) to /sdcard/Mod/
2/ copy modified deodexed files (.apk and .jar) in /system/framework/ of your GS2

Now we are going to odex back

3/ open a CMD prompt in the folder of adb.exe (usualy /android-sdk-windows/platform-tools/)
4/ type command :


adb shell
## for .JAR file :
dexopt-wrapper /system/framework/XXX.jar /system/framework/patched_XXX.odex /system/framework/core.jar:/system/framework/bouncycastle.jar:/system/framework/ext.jar:/system/framework/framework.jar:/system/framework/android.policy.jar:/system/framework/services.jar:/system/framework/core-junit.jar

response must be :
--- BEGIN '/system/framework/android.policy.jar' (bootstrap=0) ---
--- waiting for verify+opt, pid=7194
--- would reduce privs here
--- END '/system/framework/android.policy.jar' (success) ---

## for .APK file :
dexopt-wrapper /system/framework/XXX.apk /system/framework/patched_XXX.odex /system/framework/core.jar:/system/framework/bouncycastle.jar:/system/framework/ext.jar:/system/framework/framework.jar:/system/framework/android.policy.jar:/system/framework/services.jar:/system/framework/core-junit.jar
--> This will create the patched_XXX.odex file

Now we need to copy signature from original .odex file to patched .odex file cause Dalvik need files signature integrity in order to boot.

5/ always in the same CMD prompt windows :


# if not already done ...
adb shell

# copy the original .odex and .jar in system/framework (not .apk) : 
cp /sdcard/MOD/original.XXX.odex /system/framework
cp -f /sdcard/MOD/XXX.jar /system/framework   # where XXX.jar is the original odexed .jar

# give all permissions to XXX.odex files :
chmod 777 /system/framework/original.XXX.odex
chmod 777 /system/framework/patched_XXX.odex

# copy signature :
busybox dd if=/system/framework/original.XXX.odex of=/system/framework/patched_XXX.odex bs=1 count=20 skip=52 seek=52 conv=notrunc

response must be :
busybox dd if=/system/framework/original.XXX.odex of=/system/framewor
k/patched_XXX.odex bs=1 count=20 skip=52 seek=52 conv=notrunc
20+0 records in
20+0 records out
20 bytes (20B) copied, 0.002042 seconds, 9.6KB/s
Now the signature is copied over the patched_XXX.odex

Notice :
a - if you don't have response after busybox dd command : busybox is not installed or you have a to old version, use the busybox included in the attached .zip
b - if you don't have the last response line : 20 byt