Author: veithen
Date: Thu Mar 5 23:14:56 2009
New Revision: 750669
URL: http://svn.apache.org/viewvc?rev=750669&view=rev
Log:
Allow SizeAwareDataSource#getSize() to return -1 if it is unable to determine
the size. Also added a comment about the expected accurateness of the size
information.
Modified:
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/SizeAwareDataSource.java
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/impl/BufferUtils.java
Modified:
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/SizeAwareDataSource.java
URL:
http://svn.apache.org/viewvc/webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/SizeAwareDataSource.java?rev=750669&r1=750668&r2=750669&view=diff
==============================================================================
---
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/SizeAwareDataSource.java
(original)
+++
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/SizeAwareDataSource.java
Thu Mar 5 23:14:56 2009
@@ -27,15 +27,31 @@
* Code working with data sources can use this interface to optimize certain
operations.
* An example is
* {...@link
org.apache.axiom.attachments.impl.BufferUtils#doesDataHandlerExceedLimit(javax.activation.DataHandler,
int)}.
+ * <p>
+ * Code using this interface should be aware that some implementations may be
unable to guarantee
+ * 100% accuracy when determining the size of the data source. Situations
where this can occur
+ * include:
+ * <ul>
+ * <li>The data source uses a network protocol that allows to get the size
of the data
+ * but that doesn't guarantee accurateness.</li>
+ * <li>Reading the data involves a decoding operation and the length of the
resulting stream
+ * can't be determined precisely without performing the decoding
operation. In this
+ * case the implementation of this interface may return a value based on
an estimation.</li>
+ * </ul>
+ * When reading the actual data, the code should always read until the end of
the stream is
+ * reached (as indicated by the return value of the <code>read</code> methods
of the
+ * {...@link java.io.InputStream} class). It must be prepared to reach the end
of the stream after
+ * a number of bytes that is lower or higher than the value returned by
{...@link #getSize()}.
*/
public interface SizeAwareDataSource extends DataSource {
/**
* Get the size of the data source.
* Implementations must return the number of bytes that can be read from
* the input stream returned by {...@link #getInputStream()} before
reaching
- * the end of the stream.
+ * the end of the stream. If the implementation is unable to determine the
+ * size, it must return -1.
*
- * @return the size of the data source
+ * @return the size of the data source or -1 if the size is not known
*/
long getSize();
}
Modified:
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/impl/BufferUtils.java
URL:
http://svn.apache.org/viewvc/webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/impl/BufferUtils.java?rev=750669&r1=750668&r2=750669&view=diff
==============================================================================
---
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/impl/BufferUtils.java
(original)
+++
webservices/commons/trunk/modules/axiom/modules/axiom-api/src/main/java/org/apache/axiom/attachments/impl/BufferUtils.java
Thu Mar 5 23:14:56 2009
@@ -279,8 +279,12 @@
}
DataSource ds = dh.getDataSource();
if (ds instanceof SizeAwareDataSource) {
- return ((SizeAwareDataSource)ds).getSize() > limit ? 1 : 0;
- } else if (ds instanceof javax.mail.util.ByteArrayDataSource) {
+ long size = ((SizeAwareDataSource)ds).getSize();
+ if (size != -1) {
+ return size > limit ? 1 : 0;
+ }
+ }
+ if (ds instanceof javax.mail.util.ByteArrayDataSource) {
// Special optimization for JavaMail's ByteArrayDataSource
(Axiom's ByteArrayDataSource
// already implements SizeAwareDataSource and doesn't need further
optimization):
// we know that ByteArrayInputStream#available() directly returns
the size of the
