此异常通常是由于使用了不支持的证书格式引起的。解决方法是将证书转换为支持的格式。以下是使用Java代码进行转换的示例：

import java.io.FileInputStream;
import java.security.KeyStore;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.util.Collections;

public class TrustStoreConverter {

    public static final String PKCS12_TYPE = "pkcs12";
    public static final String X509_TYPE = "x509";

    public static void main(String[] args) throws Exception {
        String trustStorePath = args[0];
        String trustStoreType = args.length > 1 ? args[1] : PKCS12_TYPE;
        String certificateType = args.length > 2 ? args[2] : X509_TYPE;
        String trustStorePassword = args.length > 3 ? args[3] : "";

        KeyStore trustStore = KeyStore.getInstance(trustStoreType);
        trustStore.load(null, trustStorePassword.toCharArray());

        FileInputStream fis = new FileInputStream(trustStorePath);
        CertificateFactory cf = CertificateFactory.getInstance(certificateType);
        X509Certificate certificate = (X509Certificate) cf.generateCertificate(fis);

        trustStore.setCertificateEntry("alias", certificate);

        trustStore.store(System.out, trustStorePassword.toCharArray());
    }
}

上述代码中的trustStorePath，trustStoreType，certificateType和trustStorePassword是通过命令行参数传递的。您可以根据需要进行修改。运行该代码时，将生成转换后的密钥库，并将其输出到控制台。您可以将其保存到文件中以供以后使用。