liquibase-core/src/main/java/liquibase/util/StringClauses.java
public StringClauses replaceIfExists(String key, String newValue) throws IllegalArgumentException {
        if (contains(key)) {
            return replaceImpl(key, StringUtil.trimToEmpty(newValue));
        } else {
            return this;
        }
    }
public StringClauses replaceIfExists(String key, String newValue) throws IllegalArgumentException {
        if (contains(key)) {
            return replaceImpl(key, StringUtil.trimToEmpty(newValue));
        } else {
            return this;
        }
    }
Replaces the given key with a new string. If the existing key does not exist, throws IllegalArgumentException