* While it would be preferable to have this class extend * PrintWriter, this makes it difficult to make it work with files * (at least in my experience). *
* Copyright (c) 1998 Samuel A. Rebelsky. All rights reserved.
*
* @author Samuel A. Rebelsky
* @version 1.1 of February 1998
*/
public class SimpleOutput {
// +--------+------------------------------------------------------------
// | Fields |
// +--------+
/**
* The base Writer used for doing the actual output.
*/
protected PrintWriter base;
/**
* Are we writing to something that needs closing?
*/
protected boolean needs_closing;
// +--------------+------------------------------------------------------
// | Constructors |
// +--------------+
/**
* Build an object that can write to standard output.
*
pre: Standard output has not been modified.
*
post: The returned object writes to standard output.
*/
public SimpleOutput() {
// Use System.out, converting it as appropriate
base = new PrintWriter(System.out, true);
needs_closing = false;
} // SimpleOutput
/**
* Build an object that can write to a file. Make sure to
* call close() when you're done writing to that
* file. If the file can't be created, exits the program.
*
pre: The file can be created.
*
post: The object writes to that file.
*/
public SimpleOutput(String filename) {
// Since nothing is open, nothing needs closing.
needs_closing = false;
// Set the output to the given file.
setOutput(filename);
} // SimpleOutput
// +------------+--------------------------------------------------------
// | Finalizers |
// +------------+
// +------------------+--------------------------------------------------
// | Exported Methods |
// +------------------+
/**
* Print a boolean (truth) value.
*
pre: (none)
*
post: The value is printed to the appropriate destination.
*/
public void print(boolean b)
{
base.print(b);
} // print(boolean)
/**
* Print a character value.
*
pre: (none)
*
post: The value is printed to the appropriate destination.
*/
public void print(char c)
{
base.print(c);
} // print(char)
/**
* Print a double value.
*
pre: (none)
*
post: The value is printed to the appropriate destination.
*/
public void print(double d)
{
base.print(d);
} // print(double)
/**
* Print an array of doubles.
*
pre: (none)
*
post: The array is printed to the appropriate destination.
*/
public void print(double[] doubles)
{
// Special case: 0-length array
if (doubles.length == 0) {
print("[]");
}
// Normal case: 1 or more elements
else {
// Print the opening bracket
print("[");
// Print the first value
print(doubles[0]);
// Print all but the first value, with a comma before each value
for(int i = 1; i < doubles.length; ++i) {
print(", ");
print(doubles[i]);
} // for
// Print the closing bracket
print("]");
} // 1 or more elements
} // print(double[])
/**
* Print an integer value.
*
pre: (none)
*
post: The value is printed to the appropriate destination.
*/
public void print(int i)
{
base.print(i);
} // print(int)
/**
* Print an array of integer values.
*
pre: (none)
*
post: The array is printed to the appropriate destination in
* a simplified format.
*/
public void print(int[] iarr)
{
// Special case: 0-length array
if (iarr.length == 0) {
print("[]");
}
// Normal case: 1 or more elements
else {
// Print the opening bracket
print("[");
// Print the first value
print(iarr[0]);
// Print all but the first value, with a comma before each value
for(int i = 1; i < iarr.length; ++i) {
print(", ");
print(iarr[i]);
} // for
// Print the closing bracket
print("]");
} // 1 or more elements
} //print(int[])
/**
* Print a long value.
*
pre: (none)
*
post: The value is printed to the appropriate destination.
*/
public void print(long l)
{
base.print(l);
} // print(long)
/**
* Print a float value.
*
pre: (none)
*
post: The value is printed to the appropriate destination.
*/
public void print(float f)
{
base.print(f);
} // print(float)
/**
* Print a string value.
*
pre: (none)
*
post: The value is printed to the appropriate destination.
*/
public void print(String s)
{
base.print(s);
base.flush();
} // print(String)
/**
* Print a carriage return.
*
pre: (none)
*
post: A carriage return is printed to the appropriate destination.
*/
public void println()
{
base.println();
} //println
/**
* Print a boolean (truth) value followed by a carriage return
*
pre: (none)
*
post: The value is printlned to the appropriate destination.
*/
public void println(boolean b)
{
base.println(b);
} // println(boolean)
/**
* Print a character value followed by a carriage return.
*
pre: (none)
*
post: The value is printlned to the appropriate destination.
*/
public void println(char c)
{
base.println(c);
} // println(char)
/**
* Print a double value followed by a carriage return.
*
pre: (none)
*
post: The value and a carriage return are printed to
* the appropriate destination.
*/
public void println(double d)
{
base.println(d);
} // println(double)
/**
* Print an array of double values followed by a carriage return.
*
pre: (none)
*
post: The value and a carriage return are printed to
* the appropriate destination.
*/
public void println(double[] doubles)
{
print(doubles);
println();
} // println(double[])
/**
* Print an integer value followed by a carriage return.
*
pre: (none)
*
post: The value is printlned to the appropriate destination.
*/
public void println(int i)
{
base.println(i);
} // println(int)
/**
* Print an array of integers followed by a carriage return.
*
pre: (none)
*
post: The values and a carriage return are printed to the
* appropriate destination.
*/
public void println(int[] iarr)
{
print(iarr);
println();
} // println(int[])
/**
* Print a long value followed by a carriage return.
*
pre: (none)
*
post: The value is printlned to the appropriate destination.
*/
public void println(long l)
{
base.println(l);
} // println(long)
/**
* Print a float value followed by a carriage return.
*
pre: (none)
*
post: The value is printlned to the appropriate destination.
*/
public void println(float f)
{
base.println(f);
} // println(float)
/**
* Print a string value followed by a carriage return.
*
pre: (none)
*
post: The value is printlned to the appropriate destination.
*/
public void println(String s)
{
base.println(s);
} // println(String)
/**
* Reset the output to standard output. Not yet implemented.
*
pre: (none)
*
post: The output now goes to standard output.
*/
public void reset()
{
} // reset()
/**
* Set the output to a file. Make sure to call close() when
* you're done. If the file can't be created, exits the program.
*/
public void setOutput(String filename) {
// If the previous output needs closing, close it
if (needs_closing) {
base.flush();
base.close();
}
// Try to create an appropriate output stream. If we fail,
// crash the program.
try {
base = new PrintWriter(new FileWriter(filename));
}
catch (Exception e) {
throw new Error(e.toString());
}
// Note that this needs closing
needs_closing = true;
} // setOutput
} // SimpleOutput