--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/luan/lib/json/JsonToString.java	Wed Aug 02 19:00:24 2017 -0600
@@ -0,0 +1,110 @@
+package luan.lib.json;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Iterator;
+
+
+public final class JsonToString {
+
+	public static final class JsonException extends RuntimeException {
+		private JsonException(String msg) {
+			super(msg);
+		}
+	}
+
+	public static String toString(Object obj) throws JsonException {
+		StringBuilder sb = new StringBuilder();
+		toString(obj,sb);
+		return sb.toString();
+	}
+
+	private static void toString(Object obj,StringBuilder sb) throws JsonException {
+		if( obj == null || obj instanceof Boolean || obj instanceof Number ) {
+			sb.append(obj);
+			return;
+		}
+		if( obj instanceof String ) {
+			toString((String)obj,sb);
+			return;
+		}
+		if( obj instanceof List ) {
+			toString((List)obj,sb);
+			return;
+		}
+		if( obj instanceof Map ) {
+			toString((Map)obj,sb);
+			return;
+		}
+		throw new JsonException("can't handle type "+obj.getClass().getName());
+	}
+
+	private static void toString(final String s,StringBuilder sb) {
+		sb.append('"');
+		for( int i=0; i<s.length(); i++ ) {
+			char c = s.charAt(i);
+			switch(c) {
+			case '"':
+				sb.append("\\\"");
+				break;
+			case '\\':
+				sb.append("\\\\");
+				break;
+			case '\b':
+				sb.append("\\b");
+				break;
+			case '\f':
+				sb.append("\\f");
+				break;
+			case '\n':
+				sb.append("\\n");
+				break;
+			case '\r':
+				sb.append("\\r");
+				break;
+			case '\t':
+				sb.append("\\t");
+				break;
+			default:
+				sb.append(c);
+			}
+		}
+		sb.append('"');
+	}
+
+	private static void toString(List list,StringBuilder sb) {
+		if( list.isEmpty() ) {
+			sb.append("{}");
+			return;
+		}
+		sb.append('[');
+		toString(list.get(0),sb);
+		for( int i=1; i<list.size(); i++ ) {
+			sb.append(',');
+			toString(list.get(i),sb);
+		}
+		sb.append(']');
+		return;
+	}
+
+	private static void toString(Map map,StringBuilder sb) throws JsonException {
+		sb.append('{');
+		Iterator<Map.Entry> i = map.entrySet().iterator();
+		toString(i.next(),sb);
+		while( i.hasNext() ) {
+			sb.append(',');
+			toString(i.next(),sb);
+		}
+		sb.append('}');
+	}
+
+	private static void toString(Map.Entry entry,StringBuilder sb) throws JsonException {
+		Object key = entry.getKey();
+		if( !(key instanceof String) )
+			throw new JsonException("table keys must be strings");
+		toString((String)key,sb);
+		sb.append(':');
+		toString(entry.getValue(),sb);
+	}
+
+}