MetaInfo.java #2

/*
 * MetaInfo.java
 *
 * comments here.
 *
 * @author   Michiaki Tatsubori
 * @version  %VERSION% %DATE%
 * @see      java.lang.Object
 *
 * COPYRIGHT 1999 by Michiaki Tatsubori, ALL RIGHTS RESERVED.
 */
package openjava.mop;


import java.lang.reflect.*;
import java.io.*;
import java.util.*;
import openjava.tools.DebugOut;


/**
 * The class <code>MetaInfo</code>
 * <p>
 * For example
 * <pre>
 * </pre>
 * <p>
 *
 * @author   Michiaki Tatsubori
 * @version  1.0
 * @since    %SOFTWARE% 1.0
 * @see java.lang.Object
 */
public final class MetaInfo
{

    public static final String METACLASS_KEY = "instantiates";
    public static final String DEFAULT_METACLASS = "openjava.mop.OJClass";
    public static final String SUFFIX = "OJMI";
    public static final String FIELD_NAME = "dict";

    private Hashtable	table = new Hashtable();
    private String	packname;
    private String	simpleclassname;

    public MetaInfo( String metaclassname, String classname ) {
	table.put( METACLASS_KEY, metaclassname );
	this.simpleclassname = Environment.toSimpleName( classname );
	this.packname = Environment.toPackageName( classname );
    }

    public MetaInfo(String classname) {
	this(defaultMetaclass(classname), classname);
    }

    static String defaultMetaclass(String classname) {
        Class mc = OJSystem.getMetabind(classname);
        if (mc != null)  return mc.getName();
	return DEFAULT_METACLASS;
    }

    private String qualifiedClassName() {
	if (packname == null || packname.equals( "" ))  return simpleclassname;
        return packname + "." + simpleclassname;
    }

    public MetaInfo( Class clazz ) {
        this( clazz.getName() );
	String minfoname = clazz.getName() + SUFFIX;
	try {
	    Class minfo = Class.forName( minfoname );
	    Field f = minfo.getField( FIELD_NAME );
	    String[][] dict = (String[][]) f.get( null );
	    for (int i = 0; i < dict.length; ++i) {
		table.put( dict[i][0], dict[i][1] );
	    }
	} catch ( ClassNotFoundException e ) {
	    table.put(METACLASS_KEY, defaultMetaclass(clazz.getName()));
	} catch ( Exception e ) {
	    System.err.println( "meta information class " + minfoname  +
			        " has an illegal structure. : " + e );
	    table.put(METACLASS_KEY, defaultMetaclass(clazz.getName()));
	}
    }

    public void write( Writer destout ) throws IOException {
	PrintWriter out = new PrintWriter( destout );
	out.println( "/*this file is generated by OpenJava system.*/" );
	out.println( makePack() );
	out.println( "public final class " + simpleclassname + SUFFIX );
	out.println( "{" );
	out.println( "public static final String[][] " + FIELD_NAME + "={" );

	Enumeration key_i = keys();
	Enumeration value_i = elements();
	if (key_i.hasMoreElements()) {
	    out.print( " " );
	    printSet( out, key_i.nextElement(), value_i.nextElement() );
	}
	while (key_i.hasMoreElements()) {
	    out.print( "," );
	    printSet( out, key_i.nextElement(), value_i.nextElement() );
	}

	out.println( "};" );
	out.println( "}" );

	out.flush();
    }

    private String makePack() {
	if (packname == null || packname.equals( "" ))  return "";
	return "package " + packname + ";";
    }

    private void printSet( PrintWriter out, Object keyobj, Object valueobj ) {
        String key = (String) keyobj, value = (String) valueobj;
        out.print( "{\"" );
	out.print( toFlattenString( key ) );
	out.print( "\",\"" );
	out.print( toFlattenString( value ) );
	out.println( "\"}" );
    }

    public String put( String key, String value ) {
	return (String) table.put( key, value );
    }

    public String get( String key ) {
	return (String) table.get( key );
    }

    public Enumeration keys() {
	return table.keys();
    }

    public Enumeration elements() {
	return table.elements();
    }

    public static String toFlattenString( String src_str )  {
	StringBuffer result = null;

	/* cancel double quotes and back slashs */
	StringTokenizer canceller
	    = new StringTokenizer( src_str, "\\\"", true );
	result = new StringBuffer();

	while (canceller.hasMoreTokens()) {
	    String buf = canceller.nextToken();
	    if(buf.equals( "\\" ) || buf.equals( "\"" )){
		result.append( "\\" );
	    }
	    result.append( buf );
	}

	/* remove new line chars */
	StringTokenizer lnremover
	    = new StringTokenizer( result.toString(), "\n\r", false );
	result = new StringBuffer();

	while (lnremover.hasMoreTokens()) {
	    result.append( " " + lnremover.nextToken() );
	}

	return result.toString().trim();
    }

}