Beginner. How to extract vertex position from mesh

Troubleshooting General Help
1

How to extract vertex position from mesh
and rewrite them? I want to give vertex position like Vector3f[].
It can be through
mesh.getBuffer(VertexBuffer.Type.Position) and getData(),
but result not is Vector3f. I wrote a completely wrong code:

 Geometry box = new Geometry("Box", new Box(Vector3f.ZERO, 1, 1, 1));
 Geometry box1 = new Geometry ();
 Mesh boxmesh = new Mesh(); 
 boxmesh = box.getMesh();  
 VertexBuffer vb = new VertexBuffer();
 vb = boxmesh.getBuffer(VertexBuffer.Type.Position);
 Buffer buf=vb.getData();
 Object array;
 array = new Object();
 array = buf.array(); // exception
2

http://wiki.jmonkeyengine.org/doku.php/jme3:advanced:custom_meshes

3

In this example i do this:

Vector3f [] vertices1;
        vertices1=vertices.clone(); // Vector3f [] vertices - handle vertices for all quads
        vertices1[0]=new Vector3f(-1,0,0); // new Vector3f [] 
        cMesh.setBuffer(Type.Position, 3, BufferUtils.createFloatBuffer(vertices1)); //modify quad №2

and all quads was changed their vertex positions.

But in this example is not described how extract vertex position from mesh.

4

Instead of writing the buffer, read it?
Remember the buffer stores a row of floats and not Vector3f instances. So it’s like (x1, y1, z1, x2, y2, z2, x3, y3, z3, …) instead of (vec1, vec2, vec3), if I remember correctly.

5

there

At first have not found.

6

This way you copy all values twice. Simply modifying the buffer directly is probably less overhead.