Java 运行在android react本机项目不工作时出错

我正在尝试运行通过以下链接创建的react本机项目：

我不知道出了什么问题

得到了这个错误：

D:\reactNativeInstall\some>react-native run-android
Starting JS server...
Running adb -s 4d000b6157ee602b reverse tcp:8081 tcp:8081
Building and installing the app on the device (cd android && gradlew.bat install
Debug...
Downloading https://services.gradle.org/distributions/gradle-2.4-all.zip

Exception in thread "main" javax.net.ssl.SSLHandshakeException: sun.security.val
idator.ValidatorException: PKIX path building failed: sun.security.provider.cert
path.SunCertPathBuilderException: unable to find valid certification path to req
uested target
        at sun.security.ssl.Alerts.getSSLException(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.fatal(Unknown Source)
        at sun.security.ssl.Handshaker.fatalSE(Unknown Source)
        at sun.security.ssl.Handshaker.fatalSE(Unknown Source)
        at sun.security.ssl.ClientHandshaker.serverCertificate(Unknown Source)
        at sun.security.ssl.ClientHandshaker.processMessage(Unknown Source)
        at sun.security.ssl.Handshaker.processLoop(Unknown Source)
        at sun.security.ssl.Handshaker.process_record(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.readRecord(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.performInitialHandshake(Unknown Source
)
        at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
        at sun.security.ssl.SSLSocketImpl.startHandshake(Unknown Source)
        at sun.net.www.protocol.https.HttpsClient.afterConnect(Unknown Source)
        at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect
(Unknown Source)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown S
ource)
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown So
urce)
        at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unkn
own Source)
        at org.gradle.wrapper.Download.downloadInternal(Download.java:58)
        at org.gradle.wrapper.Download.download(Download.java:44)
        at org.gradle.wrapper.Install$1.call(Install.java:59)
        at org.gradle.wrapper.Install$1.call(Install.java:46)
        at org.gradle.wrapper.ExclusiveFileAccessManager.access(ExclusiveFileAcc
essManager.java:65)
        at org.gradle.wrapper.Install.createDist(Install.java:46)
        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:126)
        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61)
Caused by: sun.security.validator.ValidatorException: PKIX path building failed:
 sun.security.provider.certpath.SunCertPathBuilderException: unable to find vali
d certification path to requested target
        at sun.security.validator.PKIXValidator.doBuild(Unknown Source)
        at sun.security.validator.PKIXValidator.engineValidate(Unknown Source)
        at sun.security.validator.Validator.validate(Unknown Source)
        at sun.security.ssl.X509TrustManagerImpl.validate(Unknown Source)
        at sun.security.ssl.X509TrustManagerImpl.checkTrusted(Unknown Source)
        at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(Unknown Sour
ce)
        ... 21 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to
 find valid certification path to requested target
        at sun.security.provider.certpath.SunCertPathBuilder.build(Unknown Sourc
e)
        at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(Unknown
 Source)
        at java.security.cert.CertPathBuilder.build(Unknown Source)
        ... 27 more
Could not install the app on the device, read the error above for details.
Make sure you have an Android emulator running or a device connected and have
set up your Android development environment.
Go to https://facebook.github.io/react-native/docs/getting-started.html
and check the Android tab for setup instructions.

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如何解决此问题？

Hmm，这意味着它无法从

https://services.gradle.org/distributions/gradle-2.4-all.zip

。手动安装gradle 2.4是否有效？什么是gradle 2.4？我不明白你的意思。。。