Solve the problem of "suncertpathbuilderexception: unable to find valid certification path to requested target"

solve 『SunCertPathBuilderException：unable to find valid certification path to requested target』 problem

* problem

stay maven When compiling , A certificate verification error occurred , part log as follows ：

javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target 

This problem is usually when accessing maven Web sites that depend on Libraries （https Of ） when , The certificate was replaced , And then it leads to .
Why are certificates replaced ？ The possible reasons are , The proxy server acts as a middleman , stay https During transmission , Replace the server's certificate with , Then you can listen https The flow of . Usually , That's what the company does . Here, the proxy server takes advantage of https The key exchange process of the protocol , You can refer to this article : Eliminate illiteracy HTTPS and SSL/TLS agreement

Solve this problem , There are two ways .

* Method 1： by maven Add attribute maven.wagon.http.ssl.insecure=true

stay mvn Add... After the order -Dmaven.wagon.http.ssl.insecure=true. This property is to let maven Ignore security , No longer verify the server's certificate （ At this time, the server's certificate may be replaced ）.

mvn -Dmaven.wagon.http.ssl.insecure=true package

* Method 2： Add certificate to cacerts in

Environmental Science ：Windows.

cacerts It contains a lot of CA certificate , Position in Java Installation directory ： 『Java\jdk1.8.0_65\jre\lib\security\cacerts』.

Execute the following command , Add certificate to cacerts in ：

keytool.exe -importcert -file < New certificate > -keystore Java\jdk1.8.0_65\jre\lib\security\cacerts -storepass changeit

< New certificate > It can be cer Format , for example ,xxx.cer.

Executing this command will prompt you if you trust this certificate , Input yes, enter . Then the certificate is added cacerts It's in . part log as follows ：

Trust this certificate? [no]:  yes
Certificate was added to keystore

◇ About cacerts Explanation

Reference resources ： https://www.ibm.com/support/knowledgecenter/SSYKE2_8.0.0/com.ibm.java.security.component.80.doc/security-component/keytoolDocs/cacertsfile.html

A certificates file named “cacerts” resides in the security properties directory, java.home\lib\security, where java.home is the runtime environment directory (the jre directory in the SDK or the top-level directory of the Java 2 Runtime Environment).

The “cacerts” file represents a system-wide keystore with CA certificates. System administrators can configure and manage that file using keytool, specifying “jks” as the keystore type. The “cacerts” keystore file ships with several root CA certificates. The initial password of the “cacerts” keystore file is “changeit”. System administrators should change that password and the default access permission of that file when installing the SDK.

* Reference resources

https://stackoverflow.com/questions/30480086/how-to-integrate-ssl-certificates-to-the-cacerts-file-in-jre-security-folder