ComponentUtil.java

// file ComponentUtil.java 

// package <default>

// file ComponentUtil.java  

import java.applet.*;
import java.awt.*;
import java.io.*;

public class ComponentUtil extends Object{

	public static  Frame getParent( Component theComponent ) {
		// this finds the topmost ancestor parent of a component,;;
		// so that we can give that parent to dialog constructors...;;
		Component currParent = theComponent;
		Frame theFrame = null;
		while ( currParent != null ) {
			if ( currParent instanceof Frame ) {
				theFrame = (Frame) currParent;
				break;
			};
			currParent = currParent.getParent();
		};
		return theFrame;
	} // getParent


	/**
	* Sets up a dialog box that lets the user choose a file.
	* Have to copy in the ComponentUtil.java class to use the "getParent"
	* which is necessary for our FileDialog 
	*/
	static  File getSomeOldFile( Component C ) {
		File myF = null;
		Frame dFrame = ComponentUtil.getParent( C );
		FileDialog myFDialog = new FileDialog( dFrame, "hiya" );
		/* have to "import java.io.*;" to use FileDialog */;
		/* note: can append ",FileDialog.LOAD)" or ",FileDialog.SAVE)" to FileDialog constructor */;
		myFDialog.setVisible(true); // show(); deprecated
		try  {
			myF = new File( myFDialog.getDirectory(), myFDialog.getFile() );
		} catch( Exception exc ) {
			System.out.println( "Error opening file:" + exc );
		};
		return myF;
	} // getSomeOldFile


	/**
	* When given a file, this reads all its contents and puts them into a string 
	*/;
	static  String readStringFromFile( File theFile ) {
		String myReturnString;
		if ( theFile == null ) {
			myReturnString = "No File was opened";
		}
		else {
			try  {
				FileInputStream in = new FileInputStream( theFile );
				int size = (int) theFile.length();
				byte[] data = new byte [ size ];
				/* let's read in the file (which may not all arrive in one chomp...)*/;
				int bytes_read = 0;
				while ( bytes_read < size ) {
					bytes_read += in.read( data, bytes_read, size - bytes_read );
				};
				myReturnString = new String( data ); // used to be new String( data, 0 );
			} catch( Exception exc ) {
				myReturnString = "Error opening file:" + exc;
			};
		};
		return myReturnString;
	} // readStringFromFile

} // class ComponentUtil