/*
* Copyright 2013 Guidewire Software, Inc.
*/
package gw.util;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.Flushable;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.StringWriter;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.nio.CharBuffer;
import java.nio.charset.CharacterCodingException;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.nio.charset.CodingErrorAction;
import java.util.Properties;
public class StreamUtil
{
private StreamUtil() {
/* disable construction */
}
/**
* Converts the specified character sequence to bytes using UTF-8.
* @param seq the character sequence to convert
* @return the UTF-8 encoded result
*/
public static byte[] toBytes(CharSequence seq) {
try {
return seq.toString().getBytes("UTF-8");
}
catch (UnsupportedEncodingException ex) {
throw new RuntimeException(ex); // shouldn't happen since UTF-8 is supported by all JVMs per spec
}
}
/**
* Converts the specified byte array to a String using UTF-8.
* @param bytes the bytes to convert
* @return the resulting string
*/
public static String toString(byte[] bytes) {
try {
return new String(bytes, "UTF-8");
}
catch (UnsupportedEncodingException ex) {
throw new RuntimeException(ex); // shouldn't happen since UTF-8 is supported by all JVMs per spec
}
}
/**
* Converts the specified byte array to a String using UTF-8.
* @param bytes the bytes to convert
* @param offset the index of the first byte to decode
* @param length the number of bytes to decode
* @return the resulting string
*/
public static String toString(byte[] bytes, int offset, int length) {
try {
return new String(bytes, offset, length, "UTF-8");
}
catch (UnsupportedEncodingException ex) {
throw new RuntimeException(ex); // shouldn't happen since UTF-8 is supported by all JVMs per spec
}
}
/**
* Converts the specified property file text to a Properties object.
* @param propFileText the property file text in standard property file format
* @return the resulting Properties object
* @throws java.nio.charset.CharacterCodingException if invalid encoding
*/
public static Properties toProperties(String propFileText) throws CharacterCodingException {
CharsetEncoder encoder = Charset.forName("ISO-8859-1").newEncoder().onUnmappableCharacter(CodingErrorAction.REPORT);
byte[] bytes = encoder.encode(CharBuffer.wrap(propFileText)).array();
Properties props = new Properties();
try {
props.load(new ByteArrayInputStream(bytes));
}
catch (IOException ex) {
throw new RuntimeException(ex); // shouldn't happen with BAIS
}
return props;
}
/**
* Returns a reader for the specified input stream, using UTF-8 encoding.
* @param in the input stream to wrap
* @return a reader for this input stream
*/
public static Reader getInputStreamReader(InputStream in) {
return getInputStreamReader(in, "UTF-8");
}
/**
* Returns a reader for the specified input stream, using specified encoding.
* @param in the input stream to wrap
* @param charset the input stream to wrap
* @return a reader for this input stream
*/
public static Reader getInputStreamReader(InputStream in, String charset) {
try {
return new InputStreamReader(in, charset);
}
catch (UnsupportedEncodingException ex) {
throw new RuntimeException(ex); // shouldn't happen since UTF-8 is supported by all JVMs per spec
}
}
/**
* Returns a writer for the specified output stream, using UTF-8 encoding.
* @param out the output stream to wrap
* @return a writer for this output stream
*/
public static Writer getOutputStreamWriter(OutputStream out) {
try {
return new OutputStreamWriter(out, "UTF-8");
}
catch (UnsupportedEncodingException ex) {
throw new RuntimeException(ex); // shouldn't happen since UTF-8 is supported by all JVMs per spec
}
}
/**
* Returns an input stream for the specified character sequence, using UTF-8 encoding.
* @param cs the character sequence to wrap
* @return an input stream for reading the specified character sequence
*/
public static InputStream getStringInputStream(CharSequence cs) {
return new ByteArrayInputStream(toBytes(cs));
}
/**
* Returns the content of the specified input stream. The stream will be closed after calling this method.
* @param in the input stream to read
* @return the content of the input stream
* @throws java.io.IOException if an I/O error occurs
*/
public static byte[] getContent(InputStream in) throws IOException {
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
copy(in, baos);
return baos.toByteArray();
}
finally {
in.close();
}
}
/**
* Returns the content of the specified reader. The reader will be closed after calling this method.
* @param in the reader to read
* @return the content of the reader
* @throws java.io.IOException if an I/O error occurs
*/
public static String getContent(Reader in) throws IOException {
try {
StringWriter sw = new StringWriter();
copy(in, sw);
return sw.toString();
}
finally {
in.close();
}
}
/**
* Copies the content of an input stream to an output stream.
* @param in the input stream to read
* @param out the output stream to write
* @throws java.io.IOException if an I/O error occurs
*/
public static void copy(InputStream in, OutputStream out) throws IOException {
byte[] buf = new byte[1024];
while (true) {
int count = in.read(buf);
if (count < 0) {
break;
}
out.write(buf, 0, count);
}
out.flush();
}
/**
* Copies the content of an input stream to a writer.
* @param in the input stream to read
* @param writer the writer to write
* @throws java.io.IOException if an I/O error occurs
*/
public static void copy(InputStream in, Writer writer) throws IOException {
copy(getInputStreamReader(in), writer);
writer.flush();
}
/**
* Copies the content of a reader to an output stream.
* @param reader the reader to read
* @param out the output stream to write
* @throws java.io.IOException if an I/O error occurs
*/
public static void copy(Reader reader, OutputStream out) throws IOException {
copy(reader, getOutputStreamWriter(out));
out.flush();
}
/**
* Copies the content of a reader to a writer.
* @param in the reader to read
* @param out the writer to write
* @throws java.io.IOException if an I/O error occurs
*/
public static void copy(Reader in, Writer out) throws IOException {
char[] buf = new char[1024];
while (true) {
int count = in.read(buf);
if (count < 0) {
break;
}
out.write(buf, 0, count);
}
out.flush();
}
/**
* Close and swallow exception the exception. For use in finally blocks
* where the other io exceptions is what is wanted to be thrown.
*
* @param stream the streams to close
*/
public static void closeNoThrow(Closeable stream) {
if (stream != null) {
try {
stream.close();
} catch (IOException ignore) {
}
}
}
/**
* Closes the specified streams, suppressing any IOExceptions for inputstreams and readers.
* Even if an I/O exception is thrown, all streams can be considered closed.
* @param streams the streams to close
* @throws java.io.IOException if an i/o exception occurs while closing any outputstream or writer
*/
public static void close(Closeable... streams) throws IOException {
close(streams, 0);
}
private static void close(Closeable[] streams, int idx) throws IOException {
if (idx >= streams.length) {
return; // done
}
Closeable stream = streams[idx];
try {
if (stream != null) {
if (stream instanceof Flushable) {
((Flushable) stream).flush();
}
stream.close();
}
}
catch (IOException ex) {
if (! (stream instanceof InputStream || stream instanceof Reader)) {
throw ex; // ignore io exceptions for input streams and readers
}
}
finally {
close(streams, idx + 1);
}
}
}