How to coerce Groovy list into object?

Question

I'm following this blog post about using Lists and Maps as Constructors. Why does following list fail to coerce to object? ``` class Test { static class TestObject { private int a = 1; protected int b = 2; public int c = 3; int d = 4; String s = "s"; } static main(args) { def obj = [1, 2, 3, 4, 's'] as TestObject } } ``` I get this exception: ``` Caught: org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object '[1, 2, 3, 4, s]' with class 'java.util.ArrayList' to class 'in.ksharma.Test$TestObject' due to: groovy.lang.GroovyRuntimeException: Could not find matching constructor for: in.ksharma.Test$TestObject(java.lang.Integer, java.lang.Integer, java.lang.Integer, java.lang.Integer, java.lang.String) org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object '[1, 2, 3, 4, s]' with class 'java.util.ArrayList' to class 'in.ksharma.Test$TestObject' due to: groovy.lang.GroovyRuntimeException: Could not find matching constructor for: in.ksharma.…

Accepted Answer

You can use map:

```
class Test {
    static class TestObject {
        private int a = 1;
        protected int b = 2;
        public int c = 3;
        int d = 4;
        String s = "s";
    }

static main(args) {
        def o = ['a':1,b:'2',c:'3','d':5,s:'s'] as TestObject
        println o.d
    }
}
```

Will think about list in a moment.

EDIT

Hmm.. I'm not sure if it's possible with list. Only if You add an appropriate constructor. Full sample:

```
class Test {
    static class TestObject {
        TestObject() {
        }

TestObject(a,b,c,d,s) {
            this.a = a
            this.b = b
            this.c = c
            this.d = d
            this.s = s
        }

private int a = 1;
        protected int b = 2;
        public int c = 3;
        int d = 4;
        String s = "s";
    }

static main(args) {
        def obj = ['a':1,b:'2',c:'3','d':5,s:'s'] as TestObject
        assert obj.d == 5
        obj = [1, 2, 3, 6, 's'] as TestObject
        assert obj.d == 6
    }
}
```

How to coerce Groovy list into object?

Solution

Problem