Original file
=============
public Product getProduct(Node node) {
    // --- bunch of logic here ---
    if (nodeName.equals("ItemNum")) {
        product.setItemNumber(
            new Integer(StringUtils.parseInt(nodeValue, 0)));
    }
    if (nodeName.equals("AvgPrice")) {
        product.setAveragePrice(
            new Double(StringUtils.parseDouble(nodeValue, 0.0)));
    }
}

Converted file
==============
public Product getProduct(Node node) {
    // --- bunch of logic here ---
    if (msg.isSetField(ItemNum.FIELD)) {
        product.setItemNumber(msg.getInt(ItemNum.FIELD));
    }
    if (msg.isSetField(AvgPrice.FIELD)) {
        product.setAveragePrice(msg.getDouble(AvgPrice.FIELD));
    }
}

##</code><code>##

while (<STDIN>) {
    if ($_ =~ /nodeName.equals/) {
        my $line1 = $_;
        my $line2 = <STDIN>;
        my $line3 = <STDIN>;
        if ($line3 =~ /new Integer/) {
            chomp($line1);
            $_ = "$line1$line2";
            s/nodeName.equals\("(.*)"\).*product\.(.*)\(/msg.isSetField($1.FIELD)) {\n        product.$2(msg.getInt($1.FIELD))\;/;
            print $_;
        }
        elsif ($line3 =~ /new Double/) {
            chomp($line1);
            $_ = "$line1$line2";
            s/nodeName.equals\("(.*)"\).*product\.(.*)\(/msg.isSetField($1.FIELD)) {\n        product.$2(msg.getDouble($1.FIELD))\;/;
            print $_;
        }
        else {
            print $line1;
            print $line2;
            print $line3;
        }
    }
    else {
        print $_;
    }
}