Size of the configuration file keeps increasing each time ZAP is started with Java 9+

[thc202]

Steps to reproduce the issue:

1. Run ZAP (with Java 9);
2. Close ZAP and note the size of the configuration file (config.xml in home dir);
3. Restart ZAP several times and note that the size of the configuration file keeps increasing.

For example, starting with:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<config>
    <connection>
        <proxyChain/>
    </connection>
</config>

ends up in:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<config>
    <connection>
                                                        
        
        
        
        
        
        <proxyChain/>
                                                    
    
    
    
    
    
    </connection>
</config>

Remarks:
This is related to XML indentation changes in Java 9 (same behaviour with Java 10). The continuous addition of the empty lines around proxyChain seems to be a bug, lines before/after the elements config or connection are properly removed and indented, for example:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>


			<config>



    <connection><proxyChain/></connection>




</config>

is changed to:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<config>
    <connection>
        <proxyChain/>
    </connection>
</config>

(But with following saves it starts adding the new lines.)

The workaround is to disable the indentation when saving the configuration file.

ZAP
Version 2.7.0 (and older).

[thc202]

Labelled as a third-party issue (plan to raise a JDK issue), might worth apply the workaround in the meantime (or if in the end it's not a bug)?
Worth noting that with Apache Commons Configuration 2.x the issue does not happen (the DOM tree is "whitespace cleaned" before being indented).

[thc202]

Raised a PR to apply the workaround.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.