Pretty print maps and objects in #groovy

IndentWriter.groovy

import java.io.PrintWriter;
import java.io.Writer;
import org.codehaus.groovy.tools.Utilities;

public class IndentWriter extends PrintWriter
{
    protected boolean needIndent = true;
    protected String indentString;
    protected int indentLevel = 0;
    
    public IndentWriter(Writer w) { this(w, "   ", 0, true); }
    public IndentWriter(Writer w, String indent, int level, boolean needs)
    { super(w); indentString = indent; indentLevel = level; needIndent = needs }
    
    public int getIndent() { return indentLevel; }
    
    public IndentWriter plus(int i) {
        return new IndentWriter(out, indentString, indentLevel + i, needIndent);
    }
    
    public IndentWriter minus(int i) {
        return (plus(-i));
    }

    public IndentWriter next() { return plus(1); }
    public IndentWriter previous() { return minus(1); }
    
    protected void printIndent() {
        needIndent = false;
        super.print(Utilities.repeatString(indentString, indentLevel));
    }
    
    protected void checkIndent() { if (needIndent) { needIndent = false; printIndent(); }; }
    
    public void println() { super.println(); needIndent = true; }

    public void print(boolean b)  { checkIndent();  super.print(b); }
    public void print(char c)     { checkIndent();  super.print(c); }
    public void print(char[] s)   { checkIndent();  super.print(s); }
    public void print(double d)   { checkIndent();  super.print(d); }
    public void print(float f)    { checkIndent();  super.print(f); }
    public void print(int i)      { checkIndent();  super.print(i); }
    public void print(long l)     { checkIndent();  super.print(l); }
    public void print(Object obj) { checkIndent();  super.print(obj); }
    public void print(String s)   { checkIndent();  super.print(s); }
}

class PrettyWriter extends IndentWriter
{
    public PrettyWriter(Writer w) { super(w, '    ', 0, true); }
    public PrettyWriter(Writer w, String ins, int level, boolean needsIt) { super(w, ins, level, needsIt); }
    public PrettyWriter plus(int i) { return new PrettyWriter(out, indentString, indentLevel + i, needIndent) }

    public void print(Collection list) {
        println('[')
        (this + 1).withWriter { indent ->
            list.each { indent.print it ; indent.println ';' }
        }
        print(']')
    }
    public void println( Collection list) { print list; println() }

    public void print(Map map) {
        println('[')
        (this + 1).withWriter { indent ->
            map.entrySet().each {
                indent.print it.key; indent.print ' : '; (indent + 1).print it.value ; indent.println ';'
            }
        }
        print(']')
    }
    public void println(Map map) { print map; println() }
}