Could not resolve all files for configuration ':classpath'

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1

building android application using android studio, this is building pretty much fine and generating apk to install on device.
NOTE: I am working on proxy enabled network. So proxy configuration are working fine while building app from android studio.

Same application I want to build with android aosp complete build. So I included same android app source code as it is and building it using gradle wrapper (command line).
./gradlew
but this command throwing error as below:
#############################################################
FAILURE: Build failed with an exception.

  • What went wrong:
    A problem occurred configuring root project ‘WiFiSettings’.

Could not resolve all files for configuration ‘:classpath’.
Could not resolve com.android.tools.build:gradle:3.0.1.
Required by:
project :
Could not resolve com.android.tools.build:gradle:3.0.1.
Could not get resource ‘https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.pom’.
Could not GET ‘https://dl.google.com/dl/android/maven2/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.pom’.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
Could not resolve com.android.tools.build:gradle:3.0.1.
Could not get resource ‘https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.pom’.
Could not GET ‘https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.pom’.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

  • Try:
    Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

  • Get more help at https://help.gradle.org

BUILD FAILED in 1s
###########################################################

2

have same error

I can’t build an app using cordova, the problem is to get gradle.
this is the error:
A problem occurred configuring root project ‘android’.

Could not resolve all files for configuration ‘:classpath’.
Could not resolve com.android.tools.build:gradle:4.1.0.
Required by:
project :
Could not resolve com.android.tools.build:gradle:4.1.0.
Could not get resource ‘https://jcenter.bintray.com/com/android/tools/build/gradle/4.1.0/gradle-4.1.0.pom’.
Could not GET ‘https://jcenter.bintray.com/com/android/tools/build/gradle/4.1.0/gradle-4.1.0.pom’.
Connect to jcenter.bintray.com:443 [jcenter.bintray.com/108.168.243.150] failed: Connection timed out: connect

I tried using different version of gradle, same error.
Then I downloaded the related gradle and added its folder to environment variable path as GRADLE_HOME, no luck there too.

could any one help me