Class Ansi

java.lang.Object
com.strobel.io.Ansi
public class Ansi extends Object
Ansi coloring support is provided by this class.

To print "hello ansi world" in bold with blue foreground and white background: 

 Ansi ansi = new
Ansi(Ansi.Attribute.BRIGHT, Ansi.Color.BLUE, Ansi.Color.WHITE); ansi.out("hello ansi world")
same can be done as below: 
 String msg = ansi.colorize("hello ansi world"); // msg is original string wrapped with ansi
control sequences System.out.println(msg);
Ansi Support:

Ansi might not be supported on all systems. Ansi is mostly supported by all unix operating systems.

SUPPORTED is a final boolean, that can be used to check whether your console supports Ansi format;

Ansi class uses simple checks to decide whether ansi is supported or not. Sometimes it may do wrong guess. In such cases you can override its decision using following system property: -DAnsi=true or -DAnsi=false

if SUPPORTED is false, any ansi method will not produce ansi control sequences. so you can safely use: ansi.out("hello ansi world") irrespective of ansi is supported or not. if ansi is not supported, this will simply do System.out.print("hello ansi world")

  • Field Details

    • SUPPORTED

      public static final boolean SUPPORTED
      specifies whether ansi is supported or not.


      when this is false, it doesn't colorize given strings, rather than simply returns the given strings


      It tries best effort to guess whether ansi is supported or not. But you can override this value using system property "Ansi" (-DAnsi=true/false)

    • PREFIX

      private static final String PREFIX
      See Also:

    • SUFFIX

      private static final String SUFFIX
      See Also:

    • XTERM_256_SEPARATOR

      private static final String XTERM_256_SEPARATOR
      See Also:

    • SEPARATOR

      private static final String SEPARATOR
      See Also:

    • END

      private static final String END
      See Also:

    • start

      private String start

  • Constructor Details

    • Ansi

      public Ansi(Ansi.Attribute attr, Ansi.Color foreground, Ansi.Color background)
      Creates new instanceof Ansi.
      Parameters:
      attr - attribute of text, null means don't change
      foreground - foreground color of text, null means don't change
      background - background color of text, null means don't change

    • Ansi

      public Ansi(Ansi.Attribute attr, Ansi.AnsiColor foreground, Ansi.AnsiColor background)
      Creates new instanceof Ansi.
      Parameters:
      attr - attribute of text, null means don't change
      foreground - foreground color of text, null means don't change
      background - background color of text, null means don't change

    • Ansi

      public Ansi(String format)
      Creates new instanceof of ansi with specified format.

      The format syntax is 

      Attribute[;Foreground[;Background]]
      i.e, semicolon(;) separated values, where tokens are attribute, foreground and background respectively.
      if any non-trailing token in value is null, you still need to specify empty value. for example: 
      DIM;;GREEN # foreground is not specified

  • Method Details

    • init

      private void init(Ansi.Attribute attr, Ansi.AnsiColor foreground, Ansi.AnsiColor background)

    • toString

      public String toString()
      The string representation of this object. This string will be the same that is expected by Ansi(String)
      Overrides:
      toString in class Object
      Returns:
      string representation of this object

    • colorize

      public String colorize(String message)
      Wraps given message with special ansi control sequences and returns it

    • print

      public void print(PrintStream ps, String message)
      Prints colorized message to specified ps.

      if SUPPORTED is false, it prints raw message to ps

      Parameters:
      ps - stream to print
      message - message to be colorized

    • println

      public void println(PrintStream ps, String message)
      Prints colorized message to specified ps followed by newline.

      if SUPPORTED is false, it prints raw message to ps followed by newline.

      Parameters:
      ps - stream to print
      message - message to be colorized

    • format

      public void format(PrintStream ps, String format, Object... args)
      Prints formatted and colorized message to specified ps.

      if SUPPORTED is false, it prints formatted message to ps

      Parameters:
      ps - stream to print
      format - A format string whose output to be colorized
      args - Arguments referenced by the format specifiers in the format

    • out

      public void out(String message)
      Prints colorized message to System.out
      Parameters:
      message - message to be colorized

    • outLine

      public void outLine(String message)
      Prints colorized message to System.out followed by newline
      Parameters:
      message - message to be colorized

    • outFormat

      public void outFormat(String format, Object... args)
      Prints formatted and colorized format to System.out
      Parameters:
      format - A format string whose output to be colorized
      args - Arguments referenced by the format specifiers in the format

    • err

      public void err(String message)
      Prints colorized message to System.err
      Parameters:
      message - message to be colorized

    • errLine

      public void errLine(String message)
      Prints colorized message to System.err followed by newline
      Parameters:
      message - message to be colorized

    • errFormat

      public void errFormat(String format, Object... args)
      Prints formatted and colorized format to System.err
      Parameters:
      format - A format string whose output to be colorized
      args - Arguments referenced by the format specifiers in the format