由于项目需要采用minio快速搭建了一个分布式s3存储系统，为了考虑以后迁移到ceph的可能性，后端api放弃了minio的官方api而采用Amazon提供的官方s3 api，由于minio是兼容s3协议的存储系统，因此理论上可以采用aws sdk进行调用。

    下载java sdk的sample代码：

     git clone https://github.com/awslabs/aws-java-sample.git

     执行mvn package将自动下载依赖jar包和编译

     期间将遇到错误 [Maven] Can't build because of Source option 1.5 is no longer supported，解决方式是：

     将

      <properties>
          <maven.compiler.source>1.6</maven.compiler.source>
          <maven.compiler.target>1.6</maven.compiler.target>
      </properties>

     添加到pod.xml文件

     修改sample代码，将endpoint指定到内部搭建的s3地址，并且指定access_key和secret_key:

+        //AmazonS3 s3 = new AmazonS3Client();
+        AmazonS3 s3 = new AmazonS3Client(new BasicAWSCredentials("admin", "password"));
         Region usWest2 = Region.getRegion(Regions.US_WEST_2);
         s3.setRegion(usWest2);
+        s3.setEndpoint("http://192.168.101.200:31001");

 

    mvn package编译

    mvn exec:java执行

    执行期间将报

    Caused by: java.lang.NoClassDefFoundError: javax/xml/bind/DatatypeConverter的Exception，

   请在pod.xml中添加

          <dependency>
                 <groupId>javax.xml.bind</groupId>
                 <artifactId>jaxb-api</artifactId>
                 <version>2.3.0</version>
          </dependency>

    依赖

    mvn exec:java执行

    可以看到创建bucket和list bucket成功，但是往bucket中upload数据的时候，报

    java.lang.NullPointerException异常，这是由于ETag和eTag大小写导致的兼容问题，在最新的sdk版本中有修复。

    修改pod.xml中aws-sdk的version至最新版本：

      <dependency>
              <groupId>com.amazonaws</groupId>
              <artifactId>aws-java-sdk</artifactId>
              <version>1.11.497</version>
       </dependency>

    再次编译，记录运行结果：

lyh@lyh:~/Project/aws-java-sample$ mvn exec:java
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.inject.internal.cglib.core.$ReflectUtils$1 (file:/usr/share/maven/lib/guice.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of com.google.inject.internal.cglib.core.$ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------------------------------------------------------------
[INFO] Building aws-java-sample 1.0
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] >>> exec-maven-plugin:1.2.1:java (default-cli) > validate @ aws-java-sample >>>
[INFO] 
[INFO] <<< exec-maven-plugin:1.2.1:java (default-cli) < validate @ aws-java-sample <<<
[INFO] 
[INFO] 
[INFO] --- exec-maven-plugin:1.2.1:java (default-cli) @ aws-java-sample ---
===========================================
Getting Started with Amazon S3
===========================================

Creating bucket my-first-s3-bucket-49530254-b8e0-49ab-80f5-ac5d285e2cea

Listing buckets
 - dddd
 - my-first
 - my-first-s3-bucket-06f0d306-8671-4bf6-bc90-6132431e461d
 - my-first-s3-bucket-30a8e103-1f69-4656-85e2-2f2fcbd3948e
 - my-first-s3-bucket-49530254-b8e0-49ab-80f5-ac5d285e2cea

Uploading a new object to S3 from a file

Downloading an object
Content-Type: text/plain
    abcdefghijklmnopqrstuvwxyz
    01234567890112345678901234
    !@#$%^&*()-=[]{};':',.<>/?
    01234567890112345678901234
    abcdefghijklmnopqrstuvwxyz

Listing objects
 - MyObjectKey  (size = 135)

Deleting an object

Deleting bucket my-first-s3-bucket-49530254-b8e0-49ab-80f5-ac5d285e2cea