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2010-06-01T05:20:48Z

1 версия

в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== BufferedReader ==

<OL><LI>BufferedReader wraps another Reader and improves performance.</LI><LI>BufferedReader provides a readLine method to read a line of text.</LI></OL>
<p>Using BufferedReader:</p>



<source lang="java">
InputStreamReader inputStreamReader = new InputStreamReader(new FileInputStream (textFile), encoding );
BufferedReader bufferedReader = new BufferedReader (inputStreamReader);</source>



== Call the static method PressAnykey to keep to DOS window open. ==



<source lang="java">
import java.io.BufferedReader;
import java.io.InputStreamReader;
public class Main{
public static void main(String[] args) {
PressAnyKey();
}
public static void PressAnyKey() {
BufferedReader input = new BufferedReader(new InputStreamReader(System.in));
System.out.print("Press any key...");
try {
input.readLine();
} catch (Exception e) {
e.printStackTrace();
}
}
}</source>



== Create BufferedReader from FileReader ==



<source lang="java">
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
public class MainClass {
public static void main(String[] args) throws IOException {
// 1. Reading input by lines:
BufferedReader in = new BufferedReader(new FileReader("IOStreamDemo.java"));
String s, s2 = new String();
while ((s = in.readLine()) != null)
s2 += s + "\n";
in.close();
}
}</source>



== Create BufferedReader from InputStreamReader ==



<source lang="java">
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class MainClass {
public static void main(String[] args) throws IOException {
BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter a line:");
System.out.println(stdin.readLine());
}
}</source>



== Create BufferReader from InputStreamReader ==



<source lang="java">
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.ObjectOutputStream;
import java.net.Socket;
import java.util.Locale;
public class DateClient {
final static int PORT = 5000;
public static void main(String[] args) {
try {
Socket s = new Socket("localhost", PORT);
ObjectOutputStream oos;
oos = new ObjectOutputStream(s.getOutputStream());
oos.writeObject(Locale.getDefault());
InputStreamReader isr;
isr = new InputStreamReader(s.getInputStream());
BufferedReader br = new BufferedReader(isr);
System.out.println(br.readLine());
} catch (Exception e) {
System.err.println(e);
}
}
}</source>



== Create PrintWriter from BufferedWriter ==



<source lang="java">
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.EOFException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringReader;
public class MainClass {
public static void main(String[] args) throws IOException {
try {
BufferedReader in4 = new BufferedReader(new StringReader("asdf"));
PrintWriter out1 = new PrintWriter(new BufferedWriter(new FileWriter("IODemo.out")));
int lineCount = 1;
String s = null;
while((s = in4.readLine()) != null )
out1.println(lineCount++ + ": " + s);
out1.close();
} catch(EOFException e) {
System.err.println("End of stream");
}
}
}</source>



== Read content of a file ==



<source lang="java">
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
public class Main {
public static void main(String[] argv) {
readTextFile(new File("c:\\a.txt"));
}
public static String readTextFile(File filename) {
try {
BufferedReader br = new BufferedReader(new FileReader(filename));
StringBuilder sb = new StringBuilder();
String line = br.readLine();
while (line != null) {
sb.append(line + "\n");
line = br.readLine();
}
br.close();
return sb.toString();
} catch (Exception e) {
e.printStackTrace();
System.err.println(filename);
System.err.println(e);
return "";
}
}
}</source>



== Reading Text from a File ==



<source lang="java">
import java.io.BufferedReader;
import java.io.FileReader;
public class Main {
public static void main(String[] argv) throws Exception {
BufferedReader in = new BufferedReader(new FileReader("infilename"));
String str;
while ((str = in.readLine()) != null) {
System.out.println(str);
}
in.close();
}
}</source>



== Reads a text file and displays it line by line. ==



<source lang="java">
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
public class MainClass {
public static void main(String[] a) {
FileReader fr;
try {
fr = new FileReader (new File("yourFile.txt"));
BufferedReader br = new BufferedReader (fr);
String line = br.readLine();
while (line != null) {
System.out.println(line);
line = br.readLine();
}
br.close();

} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
}</source>



== Reversing a File ==



<source lang="java">
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
public class ReverseLines {
public static void main(String[] args) {
try {
BufferedReader input = new BufferedReader(new FileReader(args[0]));
ArrayList list = new ArrayList();
String line;
while ((line = input.readLine()) != null) {
list.add(line);
}
input.close();
Collections.reverse(list);
PrintWriter output = new PrintWriter(new BufferedWriter(new FileWriter(args[1])));
for (Iterator i = list.iterator(); i.hasNext();) {
output.println((String) i.next());
}
output.close();
} catch (IOException e) {
System.err.println(e);
}
}
}</source>



== Using BufferedReader to read input number from user ==



<source lang="java">
import java.io.BufferedReader;
import java.io.InputStreamReader;
public class Main {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
String input = reader.readLine();
double number = Double.parseDouble(input);
System.out.println(input + ":" + Math.sqrt(number));
reader.close();
}
}</source>

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Admin: 1 версия

в 17:44, 31 мая 2010