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JavaScript

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HTML 

              
                <div id="paper-container"></div>
<a target="_blank" href="https://www.jointjs.com">
  <img id="logo" src="https://assets.codepen.io/7589991/jj-logo-red.svg" width="200" height="50"></img>
</a>
!

CSS 

              
                #paper-container {
  position: absolute;
  right: 0;
  top: 0;
  left: 0;
  bottom: 0;
}

#logo {
  position: absolute;
  bottom: 20px;
  right: 0;
}
!

JS 

              
                const { dia, shapes } = joint;

// Paper

const paperContainer = document.getElementById("paper-container");

const graph = new dia.Graph({}, { cellNamespace: shapes });
const paper = new dia.Paper({
  model: graph,
  cellViewNamespace: shapes,
  width: "100%",
  height: "100%",

  defaultConnectionPoint: {
    name: "boundary",
    args: {
      selector: false
    }
  },
  defaultLink: (elementView) => {
    return new joint.shapes.standard.Link({});
  },
  cellViewNamespace: joint.shapes,
  gridSize: 10,
  async: true,
  sorting: joint.dia.Paper.sorting.APPROX,
  linkPinning: false,
  snapLinks: true
});

paperContainer.appendChild(paper.el);

// Example

// Three rectangles wrapped in a group
// <g><rect/><rect/><rect/></g>
const el1 = new joint.shapes.uml.Class({
    position: {
        x: 10,
        y: 70
    },
    size: {
        width: 100,
        height: 90
    }
});

const el2 = el1.clone().position(250, 30);
const el3 = el1.clone().position(250, 130);


// <g @see="target points to this group"><rect/><rect/><rect/></g>
const link1 = new joint.shapes.standard.Link({
    source: { id: el1.id },
    target: { id: el2.id, connectionPoint: { name: 'boundary', args: { extrapolate: true, selector: false }}},
    labels: [{ attrs: { text: { text: 'lookup\ndisabled', fontFamily: 'sans-serif' }}}]
});

// <g><rect @see="target points to this group" /><rect/><rect/></g>
const link2 = new joint.shapes.standard.Link({
    source: { id: el1.id },
    target: { id: el3.id, connectionPoint: { name: 'boundary', args: { extrapolate: true }}},
    labels: [{ attrs: { text: { text: 'default\nlookup', fontFamily: 'sans-serif' }}}]
});
graph.resetCells([el1, el2, el3, link1, link2]);

paper.unfreeze();
!
999px

Console