解决使用 groovy shell 导致 metaspace 增长的问题

public class GroovyScriptCachingBuilder {
    private GroovyShell shell;

    public GroovyScriptCachingBuilder() {
        this(null);
    }

    public GroovyScriptCachingBuilder(GroovyShell shell) {
        this.shell = shell;
    }

    private final Map<String, Script> scripts = new HashMap<>();

    public Script getScript(final String expression) {
        Script script;
        if (scripts.containsKey(expression)) {
            script = scripts.get(expression);
        } else {
            synchronized (scripts) {
                if (scripts.containsKey(expression)) {
                    script = scripts.get(expression);
                } else {
                    script = shell.parse(expression);
                    scripts.put(expression, script);
                }
            }
        }
        return script;
    }
}

private static GroovyScriptCachingBuilder groovyScriptCachingBuilder = new GroovyScriptCachingBuilder();


public static Object evalWithCache(Map instData, String conditionName) {

    final Binding binding = new Binding();
    instData.forEach((key, value) -> binding.setProperty(key.toString(), value));
    Script script = groovyScriptCachingBuilder.getScript(conditionName);
    synchronized (script) {
        script.setBinding(binding);
        return script.run();
    }

}