Jxpath Learning Notes

Get set reference Beanutil package and Xpath

http://commons.apache.org/'s Jxpath User ' s Guide

Loading of classes

JXPathContext context=JXPathContext.newContext( obj );
//和 xpath 的 范围确定

General value stored value

String fName=(String)context.getValue("firstName"); //setValue
//参考 http://www.blogjava.net/Good-Game/archive/2007/08/10/135739.html

General statistics and use of C for list [Id,name,.....]

Jxpathcontext context = Jxpathcontext.newcontext (c);
System.out.println (Context.getvalue ("count (. [ Name= ' oo ' and id= ' 1 ')); The number of objects Name=oo and id=1
System.out.println (Context.getvalue ("Sum" (). [ Name= ' oo ' and id= ' 1 ']/id))//Object Name=oo and id=1 all IDs are added

Get Set

Iterator threeBooks=context.iterate("books[position()<4]");
//xpath 的位置函数 position 其他函数参考 http://www.w3.org/TR/xpath　
//4 Core Function Library

XPath uses

public class Employee {
    Private Map Addressmap = new HashMap ();
    {        addressmap.put ("Home", new address (...));
        Addressmap.put ("Office", new Address (...));
    }
    Public Map getaddresses () {
      return addressmap;
    }
    ...
}
String homezipcode = (string) context. GetValue ("addresses[@name = ' home ']/zipcode");
Using the Addressmap Map key = home Address class attribute ZipCode

The entry point of XML in program and XPath

<?xml version= "1.0"?>
    <vendor>
      <location id= "store101" >
        <address>
          <street>orchard road</street>
        </address>
      </location>
      <location id= "store102" >
        <address>
          <street >tangerine drive</street>
        </address>
      </location>
    </vendor>
Class Company {
    private Container locations = null;
    Public Container getlocations () {
        if (locations = null) {
            URL url = getclass (). GetResource ("Vendor.xml");
            locations = new Xmldocumentcontainer (URL);
        }
        return locations;
    }
}
  ...
  Context = Jxpathcontext.newcontext (new company ());
  ...
  String street = (string) context.getvalue (
                "locations/vendor/location[@id = ' store102 ']//street");
Class Container Properties Locations header vendor (in XML) ...