Referencing External Parameters

Use database connection configuration as an example:

<?xml version="1.0" encoding="UTF-8"?>
<config xmlns="http://www.hasor.net/sechma/main">
    <jdbcSettings>
        <jdbcDriver>com.mysql.jdbc.Driver</jdbcDriver>
        <userName>sa</userName>
        <userPassword>password</userPassword>
    </jdbcSettings>
</config>

If you want to separate the database account and password from the configuration file, use ${KEY} placeholders in configuration values. Placeholders are read from JVM -D parameters or operating-system environment variables when configuration is loaded.

<?xml version="1.0" encoding="UTF-8"?>
<config xmlns="http://www.hasor.net/sechma/main">
    <jdbcSettings>
        <jdbcDriver>com.mysql.jdbc.Driver</jdbcDriver>
        <userName>${JDBC_USER_NAME:sa}</userName>
        <userPassword>${JDBC_USER_PWD:password}</userPassword>
    </jdbcSettings>
</config>

Pass values in either of the following ways during startup:

java -DJDBC_USER_NAME=sa -DJDBC_USER_PWD=password -jar app.jar

You can also write settings through code before startup:

AppContext appContext = Hasor.create()
        .addSettings(Settings.DefaultNameSpace, "jdbcSettings.userName", "sa")
        .addSettings(Settings.DefaultNameSpace, "jdbcSettings.userPassword", "password")
        .mainSettingWith("hconfig.xml")
        .build();