fc.io

Class Prompt

java.lang.Object

fc.io.Prompt

public class Prompt
extends Object

Prompts a user for input.

Thread safety: This class is not thread safe and higher level synchronization (or multiple instances of this class) should be used.

Version:

1.0 12/15/2001

Constructor Summary

Constructors

Constructor and Description
Prompt() Constructs a fallback object, using System.in, System.out for the input, output and error streams.
Prompt(InputStream in, PrintStream out, PrintStream err) Constructs the object using the specified input and output streams.
Prompt(Reader in, PrintWriter out, PrintWriter err) Constructs the object using the specified input and output writers.

Method Summary

Modifier and Type	Method and Description
String	ask(String str) Calls ask(String, boolean) so that a newline is not shown after the question shown to the user.
String	ask(String str, boolean newline) Shows the specified string to the user shows the input prompt to the user (to indicate the user's input is expected).
String	ask(String str, String fallback) Calls ask(String, String, boolean) so that a newline is not shown after the question shown to the user.
String	ask(String str, String fallback, boolean newline) Shows the specified string to the user shows the input prompt to the user (to indicate the user's input is expected).
String	getLastLine() Gets the latest input line that has been read.
static void	main(String[] args)
void	setError(PrintStream err)
void	setError(PrintWriter err)
void	setInput(InputStream in)
void	setInput(Reader in)
void	setOutput(PrintStream out)
void	setOutput(PrintWriter out)
void	write(String str) Immediately writes a string to the output.
void	writeln(String str) Immediately writes the specified string as a new line, to the output.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Prompt

public Prompt(Reader in,
              PrintWriter out,
              PrintWriter err)

Constructs the object using the specified input and output writers.

Parameters:

in - the BufferedReader to use for input

out - the PrintWriter to use for output

err - the PrintWriter to use for errors

Prompt

public Prompt(InputStream in,
              PrintStream out,
              PrintStream err)

Constructs the object using the specified input and output streams.

Parameters:

in - the BufferedReader to use for input

out - the PrintWriter to use for output

err - the PrintWriter to use for errors

Prompt

public Prompt()

Constructs a fallback object, using System.in, System.out for the input, output and error streams.

Method Detail

ask

public String ask(String str,
                  boolean newline)

Shows the specified string to the user shows the input prompt to the user (to indicate the user's input is expected). Keeps looping and asking the same question until a non-empty response has been typed by the user, then returns that response.

Parameters:

str - the string to show to the user

newline - whether to print a newline after the string

ask

public String ask(String str)

Calls ask(String, boolean) so that a newline is not shown after the question shown to the user.

ask

public String ask(String str,
                  String fallback,
                  boolean newline)

Shows the specified string to the user shows the input prompt to the user (to indicate the user's input is expected). Returns the fallback string if a empty response has been typed by the user, else returns the user response.

Parameters:

str - the string to show to the user

fallback - response to return if the user types in an empty response (typically by simply hitting a newline)

newline - whether to print a newline after showing the specified string to the user

ask

public String ask(String str,
                  String fallback)

Calls ask(String, String, boolean) so that a newline is not shown after the question shown to the user.

write

public void write(String str)

Immediately writes a string to the output. The prompt is written before the string.

writeln

public void writeln(String str)

Immediately writes the specified string as a new line, to the output. The prompt is written before the string.

getLastLine

public String getLastLine()

Gets the latest input line that has been read. Can return the same line multiple times if no new lines have been read since the last time this method was called. Returns null if no line has been read so far.

setInput

public void setInput(Reader in)

setInput

public void setInput(InputStream in)

setOutput

public void setOutput(PrintStream out)

setOutput

public void setOutput(PrintWriter out)

setError

public void setError(PrintStream err)

setError

public void setError(PrintWriter err)

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception