kevin@kevin-Inspiron-15-5510:~/Desktop/check_style$ cat Test.java 
package com.puppycrawl.tools.checkstyle.filters.suppressionxpathfilter;

public class Test {

    char a = '&'; // filtered violation
}
 kevin@kevin-Inspiron-15-5510:~/Desktop/check_style$ cat config.xml 
<?xml version="1.0"?>
<!DOCTYPE module PUBLIC "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN" "https://checkstyle.org/dtds/configuration_1_3.dtd">

<module name="Checker">
    <module name="TreeWalker">
        <module name="IllegalTokenText">
            <property name="format" value="[^a-zA-z0-9]*"/>
            <property name="tokens" value="CHAR_LITERAL"/>
        </module>
        <module name="SuppressionXpathFilter">
            <property name="file" value="/home/kevin/Desktop/check_style/Suppression-Xpath.xml" />
        </module>
    </module>
</module>
kevin@kevin-Inspiron-15-5510:~/Desktop/check_style$ cat Suppression-Xpath.xml 
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suppressions PUBLIC
        "-//Checkstyle//DTD SuppressionXpathFilter Experimental Configuration 1.2//EN"
        "https://checkstyle.org/dtds/suppressions_1_2_xpath_experimental.dtd">
<suppressions>
    <suppress-xpath
            files="Test.java"
            checks="IllegalTokenTextCheck"
            query="//ancestor-or-self::*"/>
</suppressions>
kevin@kevin-Inspiron-15-5510:~/Desktop/check_style$ java -jar /home/kevin/Downloads/checkstyle-10.12.3-all.jar -c config.xml Test.java
Starting audit...
Audit done.
kevin@kevin-Inspiron-15-5510:~/Desktop/check_style$