package com.inslink.sinosoft.util;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.List;

import com.amazonaws.AmazonServiceException;
import com.amazonaws.ClientConfiguration;
import com.amazonaws.Protocol;
import
 
 com.amazonaws.auth.AWSStaticCredentialsProvider;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.client.builder.AwsClientBuilder;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.Bucket;
import
 
 com.amazonaws.services.s3.model.ObjectListing;
import com.amazonaws.services.s3.model.S3Object;
import com.amazonaws.services.s3.model.S3ObjectInputStream;
import com.amazonaws.services.s3.model.S3ObjectSummary;

public class S3Sample {


    public static void main(String[] args) throws IOException {
        
            
 
//創建Amazon S3對象使用明確憑證
        BasicAWSCredentials credentials = new BasicAWSCredentials("your accesskey", "your secretkey");
        ClientConfiguration clientConfig = new ClientConfiguration();
        clientConfig.setSignerOverride("S3SignerType");//憑證驗證方式
        clientConfig.setProtocol(Protocol.HTTP);//訪問協議
        AmazonS3 s3Client = AmazonS3ClientBuilder.standard()
           .withCredentials(new AWSStaticCredentialsProvider(credentials))
                .withClientConfiguration(clientConfig)
                    .withEndpointConfiguration(
                        new AwsClientBuilder.EndpointConfiguration(//設置要用於請求的端點配置（服務端點和簽名區域）
                           "s3.yiducloud.cn",
                           "cn-north-1")).withPathStyleAccessEnabled(true)//是否使用路徑方式，是的話s3.yiducloud.cn/bucketname
                .build();

            System.out.println("Uploading a new object to S3 from a file\n");
            
            //枚舉bucket
            List<Bucket> buckets = s3Client.listBuckets();
            for (Bucket bucket : buckets) {
                System.out.println("Bucket: " + bucket.getName());
            }
            //枚舉bucket下對象
            ObjectListing objects = s3Client.listObjects("sinosoft-ocr-bucket");
            do {
                for (S3ObjectSummary objectSummary : objects.getObjectSummaries()) {
                    System.out.println("Object: " + objectSummary.getKey());
                }
                objects = s3Client.listNextBatchOfObjects(objects);
            } while (objects.isTruncated());
            
            
            //文件上傳
            try {
                    s3Client.putObject("bucketname", "keyname", new File("your file path"));
            } catch (AmazonServiceException e) {
                System.err.println(e.getErrorMessage());
                System.exit(1);
            }
            
            //文件下載
            try {
                S3Object o = s3Client.getObject("bucketname", "your file‘s keyname");
                S3ObjectInputStream s3is = o.getObjectContent();
                FileOutputStream fos = new FileOutputStream(new File("your save file path"));
                byte[] read_buf = new byte[1024];
                int read_len = 0;
                while ((read_len = s3is.read(read_buf)) > 0) {
                    fos.write(read_buf, 0, read_len);
                }
                s3is.close();
                fos.close();
            } catch (AmazonServiceException e) {
                System.err.println(e.getErrorMessage());
                System.exit(1);
            } catch (FileNotFoundException e) {
                System.err.println(e.getMessage());
                System.exit(1);
            } catch (IOException e) {
                System.err.println(e.getMessage());
                System.exit(1);
            }
            
            //其他操作方法參考：https://docs.aws.amazon.com/zh_cn/sdk-for-java/v1/developer-guide/examples-s3-objects.html
            //或者下載官網源碼
            


    }

}

Amazonaws S3 java SDK連接初探