Aws Java Transfer Utility Upload Make Public

Details: Written past; Concluding Updated on 03 January 2022 | Print E-mail

In this AWS Java SDK tutorial, I'd like to share with you some code examples for uploading files programmatically from local computer to a bucket on Amazon S3 server, with a Java console program, using AWS SDK for Java. In details, you lot will learn:

Upload a file to S3 bucket with default permission
Upload a file to S3 bucket with public read permission
Wait until the file exists (uploaded)

To follow this tutorial, you must have AWS SDK for Java installed for your Maven project.

Note : In the following lawmaking examples, the files are transferred direct from local reckoner to S3 server over HTTP.

1. Upload File to S3 Bucket with Default Permission

The post-obit code example uploads an image file to a S3 bucket in your AWS business relationship'due south default region, with default permission (owner has read-write permission; public users do not accept permission):

package net.codejava.aws;  import java.io.File;  import software.amazon.awssdk.cadre.sync.RequestBody; import software.amazon.awssdk.services.s3.S3Client; import software.amazon.awssdk.services.s3.model.PutObjectRequest;  public class UploadFileExample1 { 	public static void main(String[] args) { 		Cord bucketName = "codejava-saucepan"; 		 		String fileName = "Java Logo.png"; 		String filePath = "D:/Images/" + fileName; 		 		S3Client customer = S3Client.builder().build(); 		 		PutObjectRequest request = PutObjectRequest.builder() 							.bucket(bucketName).key(fileName).build(); 		 		client.putObject(asking, RequestBody.fromFile(new File(filePath))); 				 	} }

The code is self-explanatory - quite simple, right? The file is stored as an object in the given bucket, with object primal is the file name. If you want to put the file in a "folder", specify the key something like this:

.bucket(bucketName).fundamental("programming/java/" + fileName).build();

Too annotation that past default, the uploaded file is non attainable by public users. And the programme terminates apace as the performance is asynchronous.

2. Upload File to S3 Saucepan with Public Read Permission

In instance yous want to requite read permission for public users, i.e. the file is attainable by visitors using web browser, y'all tin can specify the public-read permission when creating a new request like this:

PutObjectRequest asking = PutObjectRequest.architect() 			.bucket(bucketName) 			.key(fileName) 			.acl("public-read").build();

Then you can utilize web browser to access the file using the following URL pattern:

https://bucket-name.s3.region-name.amazonaws.com/object-key

Replace saucepan-proper name, region-name and object-key by their actual values.

3. Set up additional information for upload file

You lot can use the contentXXX() methods of the PutObjectRequest class to specify additional information for the file stored on S3. For example, the post-obit code set content blazon of the file to be "image/png" for the file:

PutObjectRequest request = PutObjectRequest.builder() 		.bucket(bucketName) 		.primal(cardinal) 		.acl("public-read") 		.contentType("epitome/png") 		.build();

The other methods are contentDisposition(), contentEncoding(), contentLanguage(), contentLength()…

4. Expect Until the File Exists (Uploaded)

By default, the file upload performance is asynchronous. If you want to expect until the file exists (uploaded) in order to run some custom logics that depend on the existence of the file, employ a S3Waiterevery bit shown in the following code example:

package net.codejava.aws;  import coffee.io.File;  import software.amazon.awssdk.core.sync.RequestBody; import software.amazon.awssdk.core.waiters.WaiterResponse; import software.amazon.awssdk.services.s3.S3Client; import software.amazon.awssdk.services.s3.model.HeadObjectRequest; import software.amazon.awssdk.services.s3.model.HeadObjectResponse; import software.amazon.awssdk.services.s3.model.PutObjectRequest; import software.amazon.awssdk.services.s3.waiters.S3Waiter;  public class UploadFileExample3 { 	public static void master(String[] args) { 		String bucketName = "codejava-saucepan"; 		String folderName = "photos"; 		 		String fileName = "Coffee Logo.png"; 		String filePath = "D:/Images/" + fileName; 		Cord key = folderName + "/" + fileName; 		 		S3Client client = S3Client.builder().build(); 		 		PutObjectRequest request = PutObjectRequest.architect() 						.bucket(bucketName) 						.central(key) 						.acl("public-read") 						.build(); 		 		customer.putObject(request, RequestBody.fromFile(new File(filePath))); 		 		S3Waiter waiter = client.waiter(); 		HeadObjectRequest requestWait = HeadObjectRequest.builder().saucepan(bucketName).cardinal(key).build(); 		 		WaiterResponse<HeadObjectResponse> waiterResponse = waiter.waitUntilObjectExists(requestWait); 		 		waiterResponse.matched().response().ifPresent(Arrangement.out::println); 		 		Organisation.out.println("File " + fileName + " was uploaded.");		 	} }

You lot meet, the method call waitUntilObjectExists() cause the programme to wait until the file actually uploaded to S3. And then you can run your logic afterwards.

Those are some code examples near uploading files directly from local calculator to a saucepan on Amazon S3 server, using AWS SDK for Coffee. To see the coding in activity, I recommend y'all watch the following video:

About the Author:

Nam Ha Minh is certified Java programmer (SCJP and SCWCD). He started programming with Java in the time of Coffee one.4 and has been falling in beloved with Java since then. Make friend with him on Facebook and watch his Java videos you lot YouTube.

lampungmeiuaromme1969.blogspot.com

Source: https://www.codejava.net/aws/upload-file-to-s3-java-console

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