TempRaf.java

package com.onionnetworks.io;

import java.io.*;
import com.onionnetworks.util.*;

/**
 * @author Justin Chapweske (justin@chapweske.com)
 */
public class TempRaf extends FilterRAF {

    public static final int NEVER = 0;
    public static final int RENAMED_AND_DONE_WRITING = 1;
    public static final int RENAMED = 2;
    public static final int ALWAYS = 3;

    public static final int DEFAULT_KEEP_POLICY = 0;

    int keepPolicy;
    boolean renamed = false;

    public TempRaf() throws IOException {
	this(DEFAULT_KEEP_POLICY);
    }

    public TempRaf(int keepPolicy) throws IOException {
	// Create a temp file in the user temp dir, or failing that, the
	// system temp dir.
	this(new RAF(FileUtil.createTempFile(null),"rw"),keepPolicy);
    }

    public TempRaf(RAF raf) {
	this(raf,DEFAULT_KEEP_POLICY);
    }

    public TempRaf(RAF raf, int keepPolicy) {
	super(raf);
	if (keepPolicy != ALWAYS) {
	    // clean up in case of forcable shutdown.
	    raf.getFile().deleteOnExit();
	}

	this.keepPolicy = keepPolicy;
    }

    public synchronized void renameTo(File newFile) throws IOException {
	renamed = true;
	super.renameTo(newFile);
    }

    public synchronized void close() throws IOException {

	// keep as a switch statement for readability.
	switch (keepPolicy) {
	case ALWAYS:
	    break;
	case NEVER:
	    deleteOnClose();
	    break;
	case RENAMED:
	    if (!renamed) {
		deleteOnClose();
	    }
	    break;
	case RENAMED_AND_DONE_WRITING:
	    if (!renamed || !getMode().equals("r")) {
		deleteOnClose();
	    }
	    break;
	}
	    
	super.close();
    }

}