Java tutorial
package pagerank; /* * Copyright 2010-2015 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file is distributed * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either * express or implied. See the License for the specific language governing * permissions and limitations under the License. */ import java.io.BufferedReader; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.io.Writer; import java.net.URLDecoder; import java.net.URLEncoder; import java.util.HashSet; import java.util.Set; import java.util.UUID; import com.amazonaws.AmazonClientException; import com.amazonaws.AmazonServiceException; import com.amazonaws.auth.AWSCredentials; import com.amazonaws.auth.profile.ProfileCredentialsProvider; import com.amazonaws.regions.Region; import com.amazonaws.regions.Regions; 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.GetObjectRequest; import com.amazonaws.services.s3.model.ListObjectsRequest; import com.amazonaws.services.s3.model.ObjectListing; import com.amazonaws.services.s3.model.PutObjectRequest; import com.amazonaws.services.s3.model.S3Object; import com.amazonaws.services.s3.model.S3ObjectInputStream; import com.amazonaws.services.s3.model.S3ObjectSummary; /** * This sample demonstrates how to make basic requests to Amazon S3 using the * AWS SDK for Java. * <p> * <b>Prerequisites:</b> You must have a valid Amazon Web Services developer * account, and be signed up to use Amazon S3. For more information on Amazon * S3, see http://aws.amazon.com/s3. * <p> * Fill in your AWS access credentials in the provided credentials file * template, and be sure to move the file to the default location * (/home/yupenglu/.aws/credentials) where the sample code will load the credentials from. * <p> * <b>WARNING:</b> To avoid accidental leakage of your credentials, DO NOT keep * the credentials file in your source directory. * * http://aws.amazon.com/security-credentials */ public class S3Wrapper { private String bucketName; private AmazonS3 s3; private ObjectListing objectListing; private boolean isTruncated; public S3Wrapper(String bucketName) { this.bucketName = bucketName; init(); } private void init() { /* * The ProfileCredentialsProvider will return your [default] * credential profile by reading from the credentials file located at * (/home/yupenglu/.aws/credentials). */ AWSCredentials credentials = null; try { credentials = new ProfileCredentialsProvider("default").getCredentials(); } catch (Exception e) { throw new AmazonClientException("Cannot load the credentials from the credential profiles file. " + "Please make sure that your credentials file is at the correct " + "location (/home/yupenglu/.aws/credentials), and is in valid format.", e); } s3 = new AmazonS3Client(credentials); System.out.println("==========================================="); System.out.println("Getting Started with Amazon S3"); System.out.println("===========================================\n"); objectListing = s3.listObjects(new ListObjectsRequest().withBucketName(bucketName)); isTruncated = objectListing.isTruncated(); } public String get(String key) { S3Object testObj = s3.getObject(bucketName, key); S3ObjectInputStream inputStream = testObj.getObjectContent(); return streamToString(inputStream); } public Set<String> keySet() { Set<String> keySet = new HashSet<String>(); for (S3ObjectSummary summary : objectListing.getObjectSummaries()) { keySet.add(summary.getKey()); } isTruncated = objectListing.isTruncated(); objectListing = s3.listNextBatchOfObjects(objectListing); return keySet; } public Set<String> keySet(int num) { if (num < 0) return null; ObjectListing objectListing = s3.listObjects(new ListObjectsRequest().withBucketName(bucketName)); int count = num; while (count != 0) { objectListing = s3.listNextBatchOfObjects(objectListing); count--; } Set<String> keySet = new HashSet<String>(); for (S3ObjectSummary summary : objectListing.getObjectSummaries()) { keySet.add(summary.getKey()); } return keySet; } public boolean isTruncated() { return isTruncated; } public static void main(String[] args) throws IOException { /* * The ProfileCredentialsProvider will return your [default] * credential profile by reading from the credentials file located at * (/home/yupenglu/.aws/credentials). */ AWSCredentials credentials = null; try { credentials = new ProfileCredentialsProvider("default").getCredentials(); } catch (Exception e) { throw new AmazonClientException("Cannot load the credentials from the credential profiles file. " + "Please make sure that your credentials file is at the correct " + "location (/home/yupenglu/.aws/credentials), and is in valid format.", e); } AmazonS3 s3 = new AmazonS3Client(credentials); // Region usWest2 = Region.getRegion(Regions.US_WEST_2); // s3.setRegion(usWest2); // String bucketName = "my-first-s3-bucket-" + UUID.randomUUID(); String bucketName = "pages4.27"; String key = "NewKey"; System.out.println("==========================================="); System.out.println("Getting Started with Amazon S3"); System.out.println("===========================================\n"); try { /* * Create a new S3 bucket - Amazon S3 bucket names are globally unique, * so once a bucket name has been taken by any user, you can't create * another bucket with that same name. * * You can optionally specify a location for your bucket if you want to * keep your data closer to your applications or users. */ // System.out.println("Creating bucket " + bucketName + "\n"); // s3.createBucket(bucketName); /* * List the buckets in your account */ System.out.println("Listing buckets"); for (Bucket bucket : s3.listBuckets()) { System.out.println(" - " + bucket.getName()); } System.out.println(); /* * Upload an object to your bucket - You can easily upload a file to * S3, or upload directly an InputStream if you know the length of * the data in the stream. You can also specify your own metadata * when uploading to S3, which allows you set a variety of options * like content-type and content-encoding, plus additional metadata * specific to your applications. */ // System.out.println("Uploading a new object to S3 from a file\n"); // s3.putObject(new PutObjectRequest(bucketName, key, createSampleFile())); /* * Download an object - When you download an object, you get all of * the object's metadata and a stream from which to read the contents. * It's important to read the contents of the stream as quickly as * possibly since the data is streamed directly from Amazon S3 and your * network connection will remain open until you read all the data or * close the input stream. * * GetObjectRequest also supports several other options, including * conditional downloading of objects based on modification times, * ETags, and selectively downloading a range of an object. */ // System.out.println("Downloading an object"); // S3Object object = s3.getObject(new GetObjectRequest(bucketName, key)); // System.out.println("Content-Type: " + object.getObjectMetadata().getContentType()); // displayTextInputStream(object.getObjectContent()); /* * List objects in your bucket by prefix - There are many options for * listing the objects in your bucket. Keep in mind that buckets with * many objects might truncate their results when listing their objects, * so be sure to check if the returned object listing is truncated, and * use the AmazonS3.listNextBatchOfObjects(...) operation to retrieve * additional results. */ System.out.println("Listing objects"); // ObjectListing objectListing = s3.listObjects(new ListObjectsRequest() // .withBucketName(bucketName) // .withPrefix("My")); ObjectListing objectListing = s3.listObjects(new ListObjectsRequest().withBucketName(bucketName)); for (S3ObjectSummary objectSummary : objectListing.getObjectSummaries()) { System.out.println(" - " + URLDecoder.decode(objectSummary.getKey(), "UTF-8") + " " + "(size = " + objectSummary.getSize() + ")"); } S3Object testObj = s3.getObject(bucketName, URLEncoder.encode("http://finance.yahoo.com/investing-news/", "UTF-8")); S3ObjectInputStream inputStream = testObj.getObjectContent(); // System.out.println(streamToString(inputStream)); System.out.println(); /* * Delete an object - Unless versioning has been turned on for your bucket, * there is no way to undelete an object, so use caution when deleting objects. */ // System.out.println("Deleting an object\n"); // s3.deleteObject(bucketName, key); /* * Delete a bucket - A bucket must be completely empty before it can be * deleted, so remember to delete any objects from your buckets before * you try to delete them. */ // System.out.println("Deleting bucket " + bucketName + "\n"); // s3.deleteBucket(bucketName); } catch (AmazonServiceException ase) { System.out.println("Caught an AmazonServiceException, which means your request made it " + "to Amazon S3, but was rejected with an error response for some reason."); System.out.println("Error Message: " + ase.getMessage()); System.out.println("HTTP Status Code: " + ase.getStatusCode()); System.out.println("AWS Error Code: " + ase.getErrorCode()); System.out.println("Error Type: " + ase.getErrorType()); System.out.println("Request ID: " + ase.getRequestId()); } catch (AmazonClientException ace) { System.out.println("Caught an AmazonClientException, which means the client encountered " + "a serious internal problem while trying to communicate with S3, " + "such as not being able to access the network."); System.out.println("Error Message: " + ace.getMessage()); } } /** * Creates a temporary file with text data to demonstrate uploading a file * to Amazon S3 * * @return A newly created temporary file with text data. * * @throws IOException */ private static File createSampleFile() throws IOException { File file = File.createTempFile("aws-java-sdk-", ".txt"); file.deleteOnExit(); Writer writer = new OutputStreamWriter(new FileOutputStream(file)); writer.write("abcdefghijklmnopqrstuvwxyz\n"); writer.write("01234567890112345678901234\n"); writer.write("!@#$%^&*()-=[]{};':',.<>/?\n"); writer.write("01234567890112345678901234\n"); writer.write("abcdefghijklmnopqrstuvwxyz\n"); writer.close(); return file; } /** * Displays the contents of the specified input stream as text. * * @param input * The input stream to display as text. * * @throws IOException */ private static void displayTextInputStream(InputStream input) throws IOException { BufferedReader reader = new BufferedReader(new InputStreamReader(input)); while (true) { String line = reader.readLine(); if (line == null) break; System.out.println(" " + line); } System.out.println(); } // private static String streamToString(S3ObjectInputStream inputStream) { // InputStreamReader in = new InputStreamReader(inputStream); // StringBuffer buffer = new StringBuffer(); // int c; // try { // while ((c = in.read()) != -1) { // buffer.append((char)c); // } // } catch (IOException e) { // e.printStackTrace(); // } // return buffer.toString(); // } private String streamToString(S3ObjectInputStream inputStream) { InputStreamReader in = new InputStreamReader(inputStream); StringBuffer buffer = new StringBuffer(); int c; try { while ((c = in.read()) != -1) { buffer.append((char) c); } } catch (IOException e) { e.printStackTrace(); } return buffer.toString(); } }