try {
// 1. Buffered input file
DataInputStream in =
new DataInputStream(
new BufferedInputStream(
new FileInputStream(args[0])));
String s, s2 = new String();
while((s = in.readLine())!= null)
s2 += s + "\n";
in.close();
// 2. Input from memory
StringBufferInputStream in2 =
new StringBufferInputStream(s2);
int c;
while((c = in2.read()) != -1)
System.out.print((char)c);
// 3. Formatted memory input
try {
DataInputStream in3 =
new DataInputStream(
new StringBufferInputStream(s2));
while(true)
System.out.print((char)in3.readByte());
} catch(EOFException e) {
System.out.println(
"End of stream encountered");
}
// 4. Line numbering & file output
try {
LineNumberInputStream li =
new LineNumberInputStream(
new StringBufferInputStream(s2));
DataInputStream in4 =
new DataInputStream(li);
PrintStream out1 =
new PrintStream(
new BufferedOutputStream(
new FileOutputStream(
"IODemo.out")));
while((s = in4.readLine()) != null )
out1.println(
"Line " + li.getLineNumber() + s);
out1.close(); // finalize() not reliable!
} catch(EOFException e) {
System.out.println(
"End of stream encountered");
}
// 5. Storing & recovering data
try {
DataOutputStream out2 =
new DataOutputStream(
new BufferedOutputStream(
new FileOutputStream("Data.txt")));
out2.writeBytes(
"Here's the value of pi: \n");
out2.writeDouble(3.14159);
out2.close();
DataInputStream in5 =
new DataInputStream(
new BufferedInputStream(
new FileInputStream("Data.txt")));
System.out.println(in5.readLine());
System.out.println(in5.readDouble());
} catch(EOFException e) {
System.out.println(
"End of stream encountered");
}
// 6. Reading/writing random access files
RandomAccessFile rf =
new RandomAccessFile("rtest.dat", "rw");
for(int i = 0; i < 10; i++)
rf.writeDouble(i*1.414);
rf.close();
rf =
new RandomAccessFile("rtest.dat", "rw");
rf.seek(5*8);
rf.writeDouble(47.0001);
rf.close();
rf =
new RandomAccessFile("rtest.dat", "r");
for(int i = 0; i < 10; i++)
System.out.println(
"Value " + i + ": " +
rf.readDouble());
rf.close();
// 7. File input shorthand
InFile in6 = new InFile(args[0]);
String s3 = new String();
System.out.println(
"First line in file: " +
in6.readLine());
in6.close();
// 8. Formatted file output shorthand
PrintFile out3 = new PrintFile("Data2.txt");
out3.print("Test of PrintFile");
out3.close();
// 9. Data file output shorthand
OutFile out4 = new OutFile("Data3.txt");
out4.writeBytes("Test of outDataFile\n\r");
out4.writeChars("Test of outDataFile\n\r");
out4.close();
} catch(FileNotFoundException e) {
System.out.println(
"File Not Found:" + args[0]);
} catch(IOException e) {
System.out.println("IO Exception");
}
