学到这一步，就可以和操作系统的一些IO调用结合起来了。
感觉到设计系统和语言的人是多么的牛X。
能考虑到的细节是多么的复杂！
下一步，
file io和socket~~~~
看书的深度和系统性，还是一篇网上的文章无法比的！
致敬！
![eeef825aeb66e906723284cf5931a5ff94d72ac8]()
package com.ronsoft.books.nio.channels;
import java.nio.ByteBuffer;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.WritableByteChannel;
import java.nio.channels.Channels;
import java.io.IOException;
import java.nio.channels.GatheringByteChannel;
import java.io.FileOutputStream;
import java.util.Random;
import java.util.List;
import java.util.LinkedList;
public class ChannelCopy {
private static final String DEMOGRAPHIC = "blahblah.txt";
public static void main(String[] args) throws Exception {
// TODO Auto-generated method stub
/*
ReadableByteChannel source = Channels.newChannel(System.in);
WritableByteChannel dest = Channels.newChannel(System.out);
channelCopy1(source, dest);
// channelCopy2(source, dest);
source.close();
dest.close();
*/
int reps = 10;
if (args.length > 0) {
reps = Integer.parseInt(args[0]);
}
FileOutputStream fos = new FileOutputStream(DEMOGRAPHIC);
GatheringByteChannel gatherChannel = fos.getChannel();
ByteBuffer []bs = utterBS(reps);
while (gatherChannel.write(bs) > 0) {
}
System.out.println("Mindshare paradigms synergized to " + DEMOGRAPHIC);
fos.close();
}
private static void channelCopy1(ReadableByteChannel src,
WritableByteChannel dest) throws IOException{
ByteBuffer buffer = ByteBuffer.allocate(16 * 1024);
while (src.read(buffer) != -1) {
buffer.flip();
dest.write(buffer);
buffer.compact();
}
buffer.flip();
while (buffer.hasRemaining()) {
dest.write(buffer);
}
}
private static void channelCopy2(ReadableByteChannel src,
WritableByteChannel dest) throws IOException {
ByteBuffer buffer = ByteBuffer.allocate(10 * 1024);
while (src.read(buffer) != -1) {
buffer.flip();
while (buffer.hasRemaining()) {
dest.write(buffer);
}
buffer.clear();
}
}
private static String []col1 = {
"Aggregate", "Enable", "Leverage",
"Facilitate", "Synergize", "Repurpose",
"Strategize", "Reinvent", "Harness"
};
private static String []col2 = {
"cross-platform", "best-of-breed", "frictionless",
"ubiquitous", "extensible", "compelling",
"mission-critical", "collaborative", "integrated"
};
private static String [] col3 = {
"methodologies", "infomediaries", "platforms",
"schemas", "mindshare", "paradigms",
"functionalities", "web services", "infrastructures"
};
private static String newLine = System.getProperty("line.separator");
@SuppressWarnings({ "unchecked", "rawtypes" })
private static ByteBuffer []utterBS(int howMany) throws Exception {
List list = new LinkedList();
for (int i = 0; i < howMany; i++) {
list.add(pickRandom(col1, " "));
list.add(pickRandom(col2, " "));
list.add(pickRandom(col3, newLine));
}
ByteBuffer []bufs = new ByteBuffer[list.size()];
list.toArray(bufs);
return (bufs);
}
private static Random rand = new Random();
private static ByteBuffer pickRandom(String []strings, String suffix) throws Exception {
String string = strings[rand.nextInt(strings.length)];
int total = string.length() + suffix.length();
ByteBuffer buf = ByteBuffer.allocate(total);
buf.put(string.getBytes("US-ASCII"));
buf.put(suffix.getBytes("US-ASCII"));
buf.flip();
return (buf);
}
}
