java s3_JAVA S3 Example

最近听了一次亮哥他们AWS的首次session，中间稍微提到了一下IAM account的access key。没想到在项目中给别人code review的时候就接触到了，是针对AWS S3的。具体S3说明，见http://aws.amazon.com/s3/

Setting up project

1. AWS SDK for Java

com.amazonaws

aws-java-sdk

1.9.2

2. 使用一个IAM account，如果没有创建一个，获取到它的“Access key”和“Secret Access Key”。

Authenticate with Amazon S3

1. 使用Access Key进行验证

1) 环境变量Environment Variables – AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY.

2) Java System Properties – aws.accessKeyId and aws.secretKey.

3) 默认用户下profiles文件， ~/.aws/credentials

[default]

aws_access_key_id={YOUR_ACCESS_KEY_ID}

aws_secret_access_key={YOUR_SECRET_ACCESS_KEY}

[profile2]

...

4) 代码中直接填写

前三种使用验证链：

AmazonS3 s3Client = new AmazonS3Client();

//or

//The following line of code is effectively equivalent to the preceding example:

AmazonS3 s3Client = new AmazonS3Client(new DefaultAWSCredentialsProviderChain());

第四种：

AWSCredentials credentials = new BasicAWSCredentials("YourAccessKeyID", "YourSecretAccessKey");

AmazonS3 s3client = new AmazonS3Client(credentials);

2. 从AWS Security Token Service (AWS STS) 获取临时证书，见Document

SDK Example

import java.io.ByteArrayInputStream;

import java.io.File;

import java.io.InputStream;

import java.util.List;

import com.amazonaws.auth.AWSCredentials;

import com.amazonaws.auth.BasicAWSCredentials;

import com.amazonaws.services.s3.AmazonS3;

import com.amazonaws.services.s3.AmazonS3Client;

import com.amazonaws.services.s3.model.Bucket;

import com.amazonaws.services.s3.model.CannedAccessControlList;

import com.amazonaws.services.s3.model.ObjectMetadata;

import com.amazonaws.services.s3.model.PutObjectRequest;

import com.amazonaws.services.s3.model.S3ObjectSummary;

public class AmazonS3Example {

private static final String SUFFIX = "/";

public static void main(String[] args) {

// credentials object identifying user for authentication

// user must have AWSConnector and AmazonS3FullAccess for

// this example to work

AWSCredentials credentials = new BasicAWSCredentials(

"YourAccessKeyID",

"YourSecretAccessKey");

// create a client connection based on credentials

AmazonS3 s3client = new AmazonS3Client(credentials);

// create bucket - name must be unique for all S3 users

String bucketName = "javatutorial-net-example-bucket";

s3client.createBucket(bucketName);

// list buckets

for (Bucket bucket : s3client.listBuckets()) {

System.out.println(" - " + bucket.getName());

}

// create folder into bucket

String folderName = "testfolder";

createFolder(bucketName, folderName, s3client);

// upload file to folder and set it to public

String fileName = folderName + SUFFIX + "testvideo.mp4";

s3client.putObject(new PutObjectRequest(bucketName, fileName,

new File("C:\\Users\\user\\Desktop\\testvideo.mp4"))

.withCannedAcl(CannedAccessControlList.PublicRead));

deleteFolder(bucketName, folderName, s3client);

// deletes bucket

s3client.deleteBucket(bucketName);

}

public static void createFolder(String bucketName, String folderName, AmazonS3 client) {

// create meta-data for your folder and set content-length to 0

ObjectMetadata metadata = new ObjectMetadata();

metadata.setContentLength(0);

// create empty content

InputStream emptyContent = new ByteArrayInputStream(new byte[0]);

// create a PutObjectRequest passing the folder name suffixed by /

PutObjectRequest putObjectRequest = new PutObjectRequest(bucketName,

folderName + SUFFIX, emptyContent, metadata);

// send request to S3 to create folder

client.putObject(putObjectRequest);

}

/**

* This method first deletes all the files in given folder and than the

* folder itself

*/

public static void deleteFolder(String bucketName, String folderName, AmazonS3 client) {

List fileList =

client.listObjects(bucketName, folderName).getObjectSummaries();

for (S3ObjectSummary file : fileList) {

client.deleteObject(bucketName, file.getKey());

}

client.deleteObject(bucketName, folderName);

}

}