Ext 1.1 's ContentPanel with BorderLayout mapping to Ext 4.x

[StutiAwasthi]

Hi....
I am in a process to convert an Ext 1.1 application into Ext 4.x application. I don't know how to write the code
for Ext.ContentPanel of Ext1.1 into Ext 4.x.... please help...
Following code needs to be written in the Ext 4.x format.

CODE SNIPPET:

layout=Ext.create('Ext.panel.Panel',{
width:500,
height:400,
layout:'border',
items: [{
region:'north',
xtype:'panel',
split:false,
initialSize: 129, //
minSize: 129, //
maxSize: 129, //
titlebar: false, //
resizeTabs:false, //
collapsible: false,
animate: false //
}, {
region:'west',
xtype:'panel',
split:true,
initialSize: 200, //
minSize: 175, //
maxSize: 600, //
titlebar: true, //
collapsible: true,
animate: true //
}, {
region:'east',
xtype:'panel',
split:true,
initialSize: 202, //
minSize: 175, //
maxSize: 400, //
titlebar: true, //
collapsible: true,
animate: true //
}, {
region:'south',
xtype:'panel',
split:false,
initialSize: 25, //
titlebar: false //
}, {
region:'center',
xtype:'panel',
titlebar:false, //
autoScroll:false,
closeOnTab: true, //
resizeTabs:true //
}],
renderTo:document.body
});

layout.beginUpdate();
layout.add('north', new Ext.ContentPanel('north', 'North'));
layout.add('south', new Ext.ContentPanel('south', 'South'));
center = layout.getRegion('center');
center.add(new Ext.ContentPanel('main', {fitToFrame:true}));

layout.getRegion('center').showPanel('main');
layout.getRegion('east').hide();
layout.getRegion('west').hide();
layout.restoreState();
layout.endUpdate();

Please suggest how to convert this code to Ext 4.x. This is a semi changed code.

[StutiAwasthi]

Does anyone know the answer to this? Please help. Its kinda URGENT!