Author: sebb
Date: Thu Mar 1 15:36:26 2012
New Revision: 1295622
URL: http://svn.apache.org/viewvc?rev=1295622&view=rev
Log:
IO-296 ReaderInputStream optimization: more efficient reading of small chunks
of data
Modified:
commons/proper/io/trunk/src/changes/changes.xml
commons/proper/io/trunk/src/main/java/org/apache/commons/io/input/ReaderInputStream.java
Modified: commons/proper/io/trunk/src/changes/changes.xml
URL:
http://svn.apache.org/viewvc/commons/proper/io/trunk/src/changes/changes.xml?rev=1295622&r1=1295621&r2=1295622&view=diff
==============================================================================
--- commons/proper/io/trunk/src/changes/changes.xml (original)
+++ commons/proper/io/trunk/src/changes/changes.xml Thu Mar 1 15:36:26 2012
@@ -40,6 +40,9 @@ The <action> type attribute can be add,u
<body>
<release version="2.2" date="TBA">
+ <action dev="sebb" type="update" issue="IO-296" due-to="Oleg
Kalnichevski">
+ ReaderInputStream optimization: more efficient reading of small chunks
of data
+ </action>
<action dev="sebb" type="fix" issue="IO-298" due-to="Christian Schulte">
Various methods of class 'org.apache.commons.io.FileUtils' incorrectly
suppress 'java.io.IOException'
</action>
Modified:
commons/proper/io/trunk/src/main/java/org/apache/commons/io/input/ReaderInputStream.java
URL:
http://svn.apache.org/viewvc/commons/proper/io/trunk/src/main/java/org/apache/commons/io/input/ReaderInputStream.java?rev=1295622&r1=1295621&r2=1295622&view=diff
==============================================================================
---
commons/proper/io/trunk/src/main/java/org/apache/commons/io/input/ReaderInputStream.java
(original)
+++
commons/proper/io/trunk/src/main/java/org/apache/commons/io/input/ReaderInputStream.java
Thu Mar 1 15:36:26 2012
@@ -92,7 +92,7 @@ public class ReaderInputStream extends I
* as it is only used to transfer data from the decoder to the
* buffer provided by the caller.
*/
- private final ByteBuffer encoderOut = ByteBuffer.allocate(128);
+ private final ByteBuffer encoderOut;
private CoderResult lastCoderResult;
private boolean endOfInput;
@@ -119,8 +119,10 @@ public class ReaderInputStream extends I
public ReaderInputStream(Reader reader, CharsetEncoder encoder, int
bufferSize) {
this.reader = reader;
this.encoder = encoder;
- encoderIn = CharBuffer.allocate(bufferSize);
- encoderIn.flip();
+ this.encoderIn = CharBuffer.allocate(bufferSize);
+ this.encoderIn.flip();
+ this.encoderOut = ByteBuffer.allocate(128);
+ this.encoderOut.flip();
}
/**
@@ -181,6 +183,26 @@ public class ReaderInputStream extends I
this(reader, Charset.defaultCharset());
}
+ private void fillBuffer() throws IOException {
+ if (!endOfInput && (lastCoderResult == null ||
lastCoderResult.isUnderflow())) {
+ encoderIn.compact();
+ int position = encoderIn.position();
+ // We don't use Reader#read(CharBuffer) here because it is more
efficient
+ // to write directly to the underlying char array (the default
implementation
+ // copies data to a temporary char array).
+ int c = reader.read(encoderIn.array(), position,
encoderIn.remaining());
+ if (c == -1) {
+ endOfInput = true;
+ } else {
+ encoderIn.position(position+c);
+ }
+ encoderIn.flip();
+ }
+ encoderOut.compact();
+ lastCoderResult = encoder.encode(encoderIn, encoderOut, endOfInput);
+ encoderOut.flip();
+ }
+
/**
* Read the specified number of bytes into an array.
*
@@ -195,31 +217,15 @@ public class ReaderInputStream extends I
public int read(byte[] b, int off, int len) throws IOException {
int read = 0;
while (len > 0) {
- if (encoderOut.position() > 0) {
- encoderOut.flip();
+ if (encoderOut.hasRemaining()) {
int c = Math.min(encoderOut.remaining(), len);
encoderOut.get(b, off, c);
off += c;
len -= c;
read += c;
- encoderOut.compact();
} else {
- if (!endOfInput && (lastCoderResult == null ||
lastCoderResult.isUnderflow())) {
- encoderIn.compact();
- int position = encoderIn.position();
- // We don't use Reader#read(CharBuffer) here because it is
more efficient
- // to write directly to the underlying char array (the
default implementation
- // copies data to a temporary char array).
- int c = reader.read(encoderIn.array(), position,
encoderIn.remaining());
- if (c == -1) {
- endOfInput = true;
- } else {
- encoderIn.position(position+c);
- }
- encoderIn.flip();
- }
- lastCoderResult = encoder.encode(encoderIn, encoderOut,
endOfInput);
- if (endOfInput && encoderOut.position() == 0) {
+ fillBuffer();
+ if (endOfInput && !encoderOut.hasRemaining()) {
break;
}
}
@@ -249,8 +255,16 @@ public class ReaderInputStream extends I
*/
@Override
public int read() throws IOException {
- byte[] b = new byte[1];
- return read(b) == -1 ? -1 : b[0] & 0xFF;
+ for (;;) {
+ if (encoderOut.hasRemaining()) {
+ return encoderOut.get() & 0xFF;
+ } else {
+ fillBuffer();
+ if (endOfInput && !encoderOut.hasRemaining()) {
+ return -1;
+ }
+ }
+ }
}
/**
