# PutPolicy
<a name="JavaApi-PutPolicy"></a>

The following Java sample shows how to use the [PutPolicy](https://docs.aws.amazon.com/privateca/latest/APIReference/API_PutPolicy.html) operation.

The operation attaches a resource-based policy to a private CA, enabling cross-account sharing. When authorized by a policy, a principal residing in another AWS account can issue and renew private end-entity certificates using a private CA that it does not own. You can find the ARN of a private CA by calling the [ListCertificateAuthorities](https://docs.aws.amazon.com/privateca/latest/APIReference/API_ListCertificateAuthorities.html) action. For examples of policies, see the AWS Private CA guidance on [Resource-Based Policies](https://docs.aws.amazon.com/privateca/latest/userguide/pca-rbp.html).

Once a policy is attached to a CA, you can inspect it with the [GetPolicy](https://docs.aws.amazon.com/privateca/latest/APIReference/API_GetPolicy.html) action or delete it with the [DeletePolicy](https://docs.aws.amazon.com/privateca/latest/APIReference/API_DeletePolicy.html) action.

```
package com.amazonaws.samples;

import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.profile.ProfileCredentialsProvider;
import com.amazonaws.client.builder.AwsClientBuilder;
import com.amazonaws.client.builder.AwsClientBuilder.EndpointConfiguration;
import com.amazonaws.auth.AWSStaticCredentialsProvider;

import com.amazonaws.services.acmpca.AWSACMPCA;
import com.amazonaws.services.acmpca.AWSACMPCAClientBuilder;

import com.amazonaws.AmazonClientException;
import com.amazonaws.services.acmpca.model.PutPolicyRequest;
import com.amazonaws.services.acmpca.model.PutPolicyResult;
import com.amazonaws.services.acmpca.model.AWSACMPCAException;
import com.amazonaws.services.acmpca.model.ConcurrentModificationException;
import com.amazonaws.services.acmpca.model.InvalidArnException;
import com.amazonaws.services.acmpca.model.InvalidStateException;
import com.amazonaws.services.acmpca.model.InvalidPolicyException;
import com.amazonaws.services.acmpca.model.LockoutPreventedException;
import com.amazonaws.services.acmpca.model.RequestFailedException;
import com.amazonaws.services.acmpca.model.ResourceNotFoundException;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;

public class PutPolicy {

    public static void main(String[] args) throws Exception {

        // Retrieve your credentials from the C:\Users\name\.aws\credentials file
        // in Windows or the .aws/credentials file in Linux.
        AWSCredentials credentials = null;
        try {
            credentials = new ProfileCredentialsProvider("default").getCredentials();
        } catch (Exception e) {
            throw new AmazonClientException("Cannot load your credentials from file.", e);
        }

        // Define the endpoint for your sample.
        String endpointRegion = "{{region}}";  // Substitute your region here, e.g. "us-west-2"
        String endpointProtocol = "https://acm-pca." + endpointRegion + ".amazonaws.com/";
        EndpointConfiguration endpoint =
            new AwsClientBuilder.EndpointConfiguration(endpointProtocol, endpointRegion);

        // Create a client that you can use to make requests.
        AWSACMPCA client = AWSACMPCAClientBuilder.standard()
            .withEndpointConfiguration(endpoint)
            .withCredentials(new AWSStaticCredentialsProvider(credentials))
            .build();

        // Create the request object.
        PutPolicyRequest req = new PutPolicyRequest();

        // Set the resource ARN.
        req.withResourceArn("arn:{{aws}}:acm-pca:{{us-east-1}}:{{111122223333}}:certificate-authority/{{11223344-1234-1122-2233-112233445566}}");

        // Import and set the policy.
        // Note: This code assumes the file "ShareResourceWithAccountPolicy.json" is in a folder titled policy.
        String policy = new String(Files.readAllBytes(Paths.get("{{policy}}", "{{ShareResourceWithAccountPolicy.json}}")));
        req.withPolicy(policy);

        // Retrieve a list of your CAs.
        PutPolicyResult result = null;
        try {
            result = client.putPolicy(req);
        } catch (ConcurrentModificationException ex) {
            throw ex;
        } catch (InvalidArnException ex) {
            throw ex;
        } catch (InvalidStateException ex) {
            throw ex;
        } catch (InvalidPolicyException ex) {
            throw ex;
        } catch (LockoutPreventedException ex) {
            throw ex;
        } catch (RequestFailedException ex) {
            throw ex;
        } catch (ResourceNotFoundException ex) {
            throw ex;
        } catch (AWSACMPCAException ex) {
            throw ex;
        }
    }
}
```