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java 嵌入groovy,在Java中嵌入Groovy(綁定)

java 嵌入groovy,在Java中嵌入Groovy(綁定)

I try to Bind Variables to Groovy and from Groovy back zu Java:

Java code:

Binding binding = new Binding();

binding.setVariable("SRESULT", "foo");

GroovyShell gs = new GroovyShell(binding);

gs.evaluate(script);

String sResult = (String) gs.getContext().getVariable("SRESULT");

System.out.println("FROM GROOVY: " + sResult);

Groovy Code:

class Est {

static SRESULT

public static void main(String[] args) {

println 'From Java: '+SRESULT

SRESULT = 'bar'

}

}

Output:

From Java: foo

FROM GROOVY: foo

My Question: I want to change SRESULT in Groovy and have access to the Value in Java.

Can anybody help me?

解決方案

The binding only applies to scripts, not to classes. If your Groovy code were a script, i.e. just the content of the main method without the surrounding class body

println 'From Java: '+SRESULT

SRESULT = 'bar'

then it would produce the result you expect. In particular you must not declare the SRESULT variable in the script, i.e.

def SRESULT = 'bar'

would not work. This is because the declarations (with def or with an explicit type) create local variables within the script, they do not assign to the binding.