Java中運行Groovy,有三種比較常用的類支持

• GroovyShell
  • 通常用來運行"script片段"或者一些零散的表達式(Expression)
• GroovyClassLoader
  • 如果腳本是一個完整的文件,特別是有API類型的時候,比如有類似于JAVA的接口,面向對象設計時,通常使用GroovyClassLoader.
• ScriptEngine
  • JSR-223應該是推薦的一種使用策略.規范化,而且簡便.

ScriptEngine

• pom.xml依賴

<dependency>
    <groupId>org.codehaus.groovy</groupId>
    <artifactId>groovy</artifactId>
    <version>2.1.6</version>
</dependency>
<dependency>
    <groupId>org.codehaus.groovy</groupId>
    <artifactId>groovy-jsr223</artifactId>
    <version>2.1.6</version>
</dependency>

• 代碼樣例

public static void evalScript() throws Exception{
    ScriptEngineManager factory = new ScriptEngineManager();
    //每次生成一個engine實例
    ScriptEngine engine = factory.getEngineByName("groovy");
    System.out.println(engine.toString());
    assert engine != null;
    //javax.script.Bindings
    Bindings binding = engine.createBindings();
    binding.put("date", new Date());
    //如果script文本來自文件,請首先獲取文件內容
    engine.eval("def getTime(){return date.getTime();}",binding);
    engine.eval("def sayHello(name,age){return 'Hello,I am ' + name + ',age' + age;}");
    Long time = (Long)((Invocable)engine).invokeFunction("getTime", null);
    System.out.println(time);
    String message = (String)((Invocable)engine).invokeFunction("sayHello", "zhangsan",new Integer(12));
    System.out.println(message);
}

• 實際案例，Java調用groovy文件里面的方法，并傳遞參數

static void simpleTest() throws IOException, InstantiationException, IllegalAccessException, ResourceException, ScriptException{
    String[] roots = new String[] { "src/main/groovy/com/mobile263/billing/groovy/" };
    //通過指定的roots來初始化GroovyScriptEngine
    GroovyScriptEngine gse = new GroovyScriptEngine(roots);
    GroovyObject groovyObject = (GroovyObject) gse.loadScriptByName("TestScript.groovy").newInstance();
    String result = (String) groovyObject.invokeMethod("output", "hello");
    System.out.println(result);
}
class TestScript {
    static String output(def str){
        println str;
        return "hello"+str;
    }
}

傳送門

Groovy入門

Groovy入門

與java的異同

與java的異同

Java嵌入Groovy

Java嵌入Groovy

數據庫

import groovy.sql.Sql;
import org.h2.tools.Server; 

    def db = Sql.newInstance('jdbc:mysql://10.200.1.6:3306/test', 'root', 'aaaaaa', 'com.mysql.jdbc.Driver');

    db.execute(''' CREATE TABLE leike(mac varchar(20) NOT NULL PRIMARY KEY)''');

    def macs = new File('shroute_inst.csv').readLines() 
    //重復的mac地址個數: 也就是這么多地址更換了平臺.
    macs.each{
        db.execute('INSERT INTO t1(c) values(?)', [it]);
    }