android - Why there are multiple copies for the same version of gradle -

i have android studio project, file gradle/wrapper/gradle-wrapper.properties configured following.

#wed apr 10 15:27:10 pdt 2013 distributionbase=gradle_user_home distributionpath=wrapper/dists zipstorebase=gradle_user_home zipstorepath=wrapper/dists distributionurl=https\://services.gradle.org/distributions/gradle-2.2.1-all.zip 

and have 2.2.1-all version installed in home directory.

.gradle/wrapper/dists/gradle-2.2.1-all/c64ydeuardnfqctvr1gm30w53/gradle-2.2.1-all.zip 

when invoke ./gradlew command build project. should use gradle-2.2.1-all.zip build.

but doesn't, download gradle same version instead. so, there 2 gradles version 2.2.1-all. because internet connection slow, takes long.

.gradle/wrapper/dists/gradle-2.2.1-all/c64ydeuardnfqctvr1gm30w53/gradle-2.2.1-all.zip .gradle/wrapper/dists/gradle-2.2.1-all/6dibv5rcnnqlfbq9klf8imrndn/gradle-2.2.1-all.zip 

it's annoying since has download new 1 same version time invoke command build project.

why gradle build system couldn't pick installed one?

the problem occurred because hash policy download url different between studio's gradle-wrapper.jar , latest gradle-wrapper.jar.

the gradle-wrapper.jar under android app directory (i guess it's copied android-sdk-macosx/tools/templates/gradle/wrapper/gradle/wrapper/gradle-wrapper.jar) use following method calculate hash download url.

// pathassembler.java private string getmd5hash(string string) {     try {         messagedigest e = messagedigest.getinstance("md5");         byte[] bytes = string.getbytes();         e.update(bytes);         return (new biginteger(1, e.digest())).tostring(32);     } catch (exception var4) {         throw new runtimeexception("could not hash input string.", var4);     } } 

but latest gradle-wrapper.jar use following method do. radix change 32 36.

private string gethash(string string) {     try {         messagedigest messagedigest = messagedigest.getinstance("md5");         byte[] bytes = string.getbytes();         messagedigest.update(bytes);         return new biginteger(1, messagedigest.digest()).tostring(36);     } catch (exception e) {         throw new runtimeexception("could not hash input string.", e);     } } 

the magic string found in directory name md5 hash string of download url.

for version 2.10, there directory name

.gradle/wrapper/dists/gradle-2.10-all/a4w5fzrkeut1ox71xslb49gst

and a4w5fzrkeut1ox71xslb49gst hashed download url.

try {     messagedigest messagedigest = messagedigest.getinstance("md5");     messagedigest.update("https://services.gradle.org/distributions/gradle-2.10-all.zip".getbytes());     system.out.println(new biginteger(1, messagedigest.digest()).tostring(36)); } catch (nosuchalgorithmexception e) {     e.printstacktrace(); } 

by using same hash method (use same gradle-wrapper.jar) same download url gradle/wrapper/gradle-wrapper.properties, there won't multiple downloads same version of gradle.

this issue exist between android studio project , other gradle project.