move xml parsing using SimpleXML

This breaks backward compatibility

api/src/main/java/io/minio/ErrorCode.java

@@ -16,10 +16,18 @@
 
 package io.minio;
 
+import org.simpleframework.xml.convert.Convert;
+import org.simpleframework.xml.convert.Converter;
+import org.simpleframework.xml.stream.InputNode;
+import org.simpleframework.xml.stream.OutputNode;
+import org.simpleframework.xml.Root;
+
 
 /**
  * Amazon AWS S3 error codes.
  */
+@Root(name = "ErrorCode")
+@Convert(ErrorCode.ErrorCodeConverter.class)
 public enum ErrorCode {
   // custom error codes
   NO_SUCH_OBJECT("NoSuchKey", "Object does not exist"),
@@ -143,21 +151,30 @@ public String message() {
     return this.message;
   }
 
+
   /**
    * Returns ErrorCode of given code string.
    */
   public static ErrorCode fromString(String codeString) {
-    if (codeString == null) {
-      return null;
-    }
-
     for (ErrorCode ec : ErrorCode.values()) {
       if (codeString.equals(ec.code)) {
         return ec;
       }
     }
 
-    // Unknown error code string.  Its not a standard Amazon S3 error.
-    return null;
+    throw new IllegalArgumentException("unknown error code string '" + codeString + "'");
+  }
+
+
+  public static class ErrorCodeConverter implements Converter<ErrorCode> {
+    @Override
+    public ErrorCode read(InputNode node) throws Exception {
+      return ErrorCode.fromString(node.getValue());
+    }
+
+    @Override
+    public void write(OutputNode node, ErrorCode errorCode) throws Exception {
+      node.setValue(errorCode.code());
+    }
   }
 }

api/src/main/java/io/minio/Result.java

@@ -18,16 +18,14 @@
 
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.databind.JsonMappingException;
-import java.io.IOException;
-import java.security.InvalidKeyException;
-import java.security.NoSuchAlgorithmException;
-
-import org.xmlpull.v1.XmlPullParserException;
-
 import io.minio.errors.ErrorResponseException;
 import io.minio.errors.InsufficientDataException;
 import io.minio.errors.InternalException;
 import io.minio.errors.InvalidBucketNameException;
+import io.minio.errors.XmlParserException;
+import java.io.IOException;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
 
 
 /**
@@ -38,8 +36,14 @@ public class Result<T> {
   private final Exception ex;
 
 
-  public Result(T type, Exception ex) {
+  public Result(T type) {
     this.type = type;
+    this.ex = null;
+  }
+
+
+  public Result(Exception ex) {
+    this.type = null;
     this.ex = ex;
   }
 
@@ -50,7 +54,7 @@ public Result(T type, Exception ex) {
   public T get()
     throws InvalidBucketNameException, NoSuchAlgorithmException, InsufficientDataException,
            JsonParseException, JsonMappingException,IOException,
-           InvalidKeyException, XmlPullParserException, ErrorResponseException,
+           InvalidKeyException, XmlParserException, ErrorResponseException,
            InternalException {
     if (ex == null) {
       return type;
@@ -72,8 +76,8 @@ public T get()
       throw (InvalidKeyException) ex;
     }
 
-    if (ex instanceof XmlPullParserException) {
-      throw (XmlPullParserException) ex;
+    if (ex instanceof XmlParserException) {
+      throw (XmlParserException) ex;
     }
 
     if (ex instanceof ErrorResponseException) {

api/src/main/java/io/minio/SelectResponseStream.java

@@ -19,6 +19,7 @@
 import io.minio.errors.InternalException;
 import io.minio.errors.MinioException;
 import io.minio.messages.Stats;
+import io.minio.messages.Progress;
 
 import java.io.ByteArrayInputStream;
 import java.io.EOFException;
@@ -140,15 +141,13 @@ private boolean populate()
     ByteArrayInputStream payloadStream = new ByteArrayInputStream(data, headerLength, payloadLength);
 
     if (headerMap.get(":event-type").equals("Progress")) {
-      Stats stats = new Stats("Progress");
-      stats.parseXml(new InputStreamReader(payloadStream, StandardCharsets.UTF_8));
+      Stats stats = (Stats) Xml.unmarshal(Progress.class, new InputStreamReader(payloadStream, StandardCharsets.UTF_8));
       this.stats = stats;
       return false;
     }
 
     if (headerMap.get(":event-type").equals("Stats")) {
-      Stats stats = new Stats("Stats");
-      stats.parseXml(new InputStreamReader(payloadStream, StandardCharsets.UTF_8));
+      Stats stats = Xml.unmarshal(Stats.class, new InputStreamReader(payloadStream, StandardCharsets.UTF_8));
       this.stats = stats;
       return false;
     }

api/src/main/java/io/minio/Xml.java

@@ -0,0 +1,86 @@
+/*
+ * MinIO Java SDK for Amazon S3 Compatible Cloud Storage,
+ * (C) 2020 MinIO, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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.
+ */
+
+package io.minio;
+
+import io.minio.errors.XmlParserException;
+import java.io.Reader;
+import java.io.StringReader;
+import java.io.StringWriter;
+import org.simpleframework.xml.convert.AnnotationStrategy;
+import org.simpleframework.xml.core.Persister;
+import org.simpleframework.xml.Serializer;
+
+
+public class Xml {
+  /**
+   * This marshal method will traverse the provided object checking for field annotations in order
+   * to compose the XML data.
+   */
+  public static String marshal(Object source) throws XmlParserException {
+    try {
+      Serializer serializer = new Persister(new AnnotationStrategy());
+      StringWriter writer = new StringWriter();
+      serializer.write(source, writer);
+      return writer.toString();
+    } catch (Exception e) {
+      throw new XmlParserException(e);
+    }
+  }
+
+
+  /**
+   * This unmarshal method will read the contents of the XML document from the provided source and
+   * populate the object with the values deserialized.
+   */
+  public static <T> T unmarshal(Class<? extends T> type, Reader source) throws XmlParserException {
+    try {
+      Serializer serializer = new Persister(new AnnotationStrategy());
+      return serializer.read(type, source);
+    } catch (Exception e) {
+      throw new XmlParserException(e);
+    }
+  }
+
+
+  /**
+   * This unmarshal method will read the contents of the XML document from the provided source and
+   * populate the object with the values deserialized.
+   */
+  public static <T> T unmarshal(Class<? extends T> type, String source) throws XmlParserException {
+    try {
+      Serializer serializer = new Persister(new AnnotationStrategy());
+      return serializer.read(type, new StringReader(source));
+    } catch (Exception e) {
+      throw new XmlParserException(e);
+    }
+  }
+
+
+  /**
+   * This validate method will validate the contents of the XML document against the specified XML
+   * class schema.
+   */
+  public static boolean validate(Class type, String source) throws XmlParserException {
+    try {
+      Serializer serializer = new Persister(new AnnotationStrategy());
+      return serializer.validate(type, source);
+    } catch (Exception e) {
+      throw new XmlParserException(e);
+    }
+  }
+}

api/src/main/java/io/minio/errors/ErrorResponseException.java

@@ -55,7 +55,7 @@ public ErrorResponse errorResponse() {
   public String toString() {
     Request request = response.request();
     return "error occurred\n"
-        + errorResponse.getString() + "\n"
+        + errorResponse.toString() + "\n"
         + "request={"
         + "method=" + request.method() + ", "
         + "url=" + request.url() + ", "

api/src/main/java/io/minio/errors/XmlParserException.java

@@ -0,0 +1,34 @@
+/*
+ * MinIO Java SDK for Amazon S3 Compatible Cloud Storage, (C) 2015 MinIO, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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.
+ */
+
+package io.minio.errors;
+
+
+public class XmlParserException extends MinioException {
+  Exception exception;
+
+
+  public XmlParserException(Exception exception) {
+    super();
+    this.exception = exception;
+  }
+
+
+  @Override
+  public String toString() {
+    return exception.toString();
+  }
+}

api/src/main/java/io/minio/messages/Bucket.java

@@ -16,26 +16,23 @@
 
 package io.minio.messages;
 
-import com.google.api.client.util.Key;
-import io.minio.Time;
 import java.time.ZonedDateTime;
-import org.xmlpull.v1.XmlPullParserException;
+import org.simpleframework.xml.Element;
+import org.simpleframework.xml.Root;
 
 
 /**
- * Helper class to parse Amazon AWS S3 response XML containing bucket information.
+ * Helper class to denote bucket information for ListAllMyBucketsResult.
  */
-@SuppressWarnings("SameParameterValue")
-public class Bucket extends XmlEntity {
-  @Key("Name")
+@Root(name = "Bucket", strict = false)
+public class Bucket {
+  @Element(name = "Name")
   private String name;
-  @Key("CreationDate")
-  private String creationDate;
+  @Element(name = "CreationDate")
+  private ResponseDate creationDate;
 
 
-  public Bucket() throws XmlPullParserException {
-    super();
-    super.name = "Bucket";
+  public Bucket() {
   }
 
 
@@ -51,6 +48,6 @@ public String name() {
    * Returns creation date.
    */
   public ZonedDateTime creationDate() {
-    return ZonedDateTime.parse(creationDate, Time.RESPONSE_DATE_FORMAT);
+    return creationDate.zonedDateTime();
   }
 }