java ssl elastic_es集群开启ssl后，java如何连接es集群

要连接开启了SSL的Elasticsearch集群，需要使用Java的TransportClient，并使用SSLContext来设置SSL连接。以下是一个简单的示例代码：

import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.TransportAddress;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentFactory;
import org.elasticsearch.transport.client.PreBuiltTransportClient;
import javax.net.ssl.SSLContext;
import java.net.InetAddress;
import java.security.KeyStore;
import java.security.SecureRandom;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;

public class ESClient {
    public static void main(String[] args) throws Exception {
        Settings settings = Settings.builder()
                .put("cluster.name", "myClusterName")
                .put("xpack.security.user", "myUsername:myPassword")
                .put("xpack.security.transport.ssl.enabled", true)
                .put("xpack.security.transport.ssl.verification_mode", "certificate")
                .put("xpack.security.transport.ssl.keystore.path", "/path/to/keystore.jks")
                .put("xpack.security.transport.ssl.truststore.path", "/path/to/truststore.jks")
                .build();

        SSLContext sslContext = SSLContext.getInstance("TLS");
        KeyStore keyStore = KeyStore.getInstance("jks");
        KeyStore trustStore = KeyStore.getInstance("jks");

        keyStore.load(ESClient.class.getResourceAsStream("/path/to/keystore.jks"), "keystore_password".toCharArray());
        trustStore.load(ESClient.class.getResourceAsStream("/path/to/truststore.jks"), "truststore_password".toCharArray());

        TrustManager[] trustManagers = new TrustManager[] { new X509TrustManager() {
            public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {}
            public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {}
            public X509Certificate[] getAcceptedIssuers() { return new X509Certificate[0]; }
        }};

        sslContext.init(null, trustManagers, new SecureRandom());

        TransportClient client = new PreBuiltTransportClient(settings)
                .addTransportAddress(new TransportAddress(InetAddress.getByName("localhost"), 9300))
                .setSSLContext(sslContext);

        XContentBuilder builder = XContentFactory.jsonBuilder();
        builder.startObject().field("name", "John").endObject();

        client.prepareIndex("myindex", "mytype", "1")
                .setSource(builder)
                .get();

        client.close();
    }
}

在这个示例代码中，我们首先使用Elasticsearch的TransportClient创建了一个连接，然后设置了连接ES集群所需的一些参数。其中，`xpack.security.user`参数是用于认证的用户名和密码，`xpack.security.transport.ssl.enabled`参数设置为`true`表示开启SSL连接，`xpack.security.transport.ssl.verification_mode`参数设置为`certificate`表示只信任CA签署的证书。最后，我们设置了keystore和truststore的路径，并使用SSLContext将其加载。

接下来，我们使用TransportClient发送了一个简单的索引请求，将一个JSON文档插入到名为`myindex`、类型为`mytype`、ID为`1`的索引中。

注意，这只是一个简单的示例，实际应用中还需要根据实际情况进行配置和调整。