[JXPATH-164] jxpath returns the wrong number of entries if a map contains an empty string value

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.3, 1.4
• Assignee: Unassigned
• Reporter: Laurent Malvert
• Created: 03/Feb/14 07:02
• Updated: 21/Nov/15 09:17

Description

It's a bit of an odd one, but I've noticed the following strange behaviors where JXPath seems to get quite confused when you have an object graph containing maps, where the map contains some objects with an
empty string:

        final JXPathContext jxp = JXPathContext.newContext(ImmutableList.<Map<String, String>>of(
                ImmutableMap.of(
                        "ID", "1",
                        "STUFF", ""
                ),
                ImmutableMap.of(
                        "ID", "2",
                        "STUFF", "42"
                ),
                ImmutableMap.of(
                        "ID", "3",
                        "STUFF", ""
                )
        ));

        assertEquals(3, jxp.selectNodes("ID").size());
        assertEquals(3, jxp.selectNodes("//ID").size());
        assertEquals(3, jxp.selectNodes("/ID").size());
        assertEquals(3, jxp.selectNodes("/.[*]/ID").size());
        assertEquals(1, jxp.selectNodes("/*/ID").size()); // SHOULD RETURN 3

Now, if you runt the same test with this:

        final JXPathContext jxp = JXPathContext.newContext(ImmutableList.<Map<String, String>>of(
                ImmutableMap.of(
                        "ID", "1"
                ),
                ImmutableMap.of(
                        "ID", "2"
                ),
                ImmutableMap.of(
                        "ID", "3"
                )
        ));

        assertEquals(3, jxp.selectNodes("ID").size());
        assertEquals(3, jxp.selectNodes("//ID").size());
        assertEquals(3, jxp.selectNodes("/ID").size());
        assertEquals(3, jxp.selectNodes("/.[*]/ID").size());
        assertEquals(0, jxp.selectNodes("/*/ID").size()); // should return 3

Notice how that last result is a 0, whereas we got a one in the first test, though the logical structure of the contextbean is the same.

And now for added fun... The odder thing is that I get slightly different behaviors for other seemingly simple datasets.

For instance, consider this data set converted to an object graph:

[ {
  "EMPNO" : "7369",
  "ENAME" : "SMITH",
  "JOB" : "test",
  "MGR" : "7902",
  "HIREDATE" : "Wed Dec 17 05:00:00 GMT 1980",
  "SAL" : "800.0",
  "COMM" : "",
  "DEPTNO" : "20"
}, {
  "EMPNO" : "7499",
  "ENAME" : "ALLEN",
  "JOB" : "SALESMAN",
  "MGR" : "7698",
  "HIREDATE" : "Fri Feb 20 05:00:00 GMT 1981",
  "SAL" : "1600.0",
  "COMM" : "300.0",
  "DEPTNO" : "30"
}, {
  "EMPNO" : "7521",
  "ENAME" : "WARD",
  "JOB" : "SALESMAN",
  "MGR" : "7698",
  "HIREDATE" : "Sun Feb 22 05:00:00 GMT 1981",
  "SAL" : "1250.0",
  "COMM" : "500.0",
  "DEPTNO" : "30"
}, {
  "EMPNO" : "7566",
  "ENAME" : "JONES",
  "JOB" : "MANAGER",
  "MGR" : "7839",
  "HIREDATE" : "Thu Apr 02 06:00:00 BST 1981",
  "SAL" : "2975.0",
  "COMM" : "",
  "DEPTNO" : "20"
}, {
  "EMPNO" : "7654",
  "ENAME" : "MARTIN",
  "JOB" : "SALESMAN",
  "MGR" : "7698",
  "HIREDATE" : "Mon Sep 28 05:00:00 BST 1981",
  "SAL" : "1250.0",
  "COMM" : "1400.0",
  "DEPTNO" : "30"
}, {
  "EMPNO" : "7698",
  "ENAME" : "BLAKE",
  "JOB" : "MANAGER",
  "MGR" : "7839",
  "HIREDATE" : "Fri May 01 05:00:00 BST 1981",
  "SAL" : "2850.0",
  "COMM" : "",
  "DEPTNO" : "30"
}, {
  "EMPNO" : "7782",
  "ENAME" : "CLARK",
  "JOB" : "MANAGER",
  "MGR" : "7839",
  "HIREDATE" : "Tue Jun 09 05:00:00 BST 1981",
  "SAL" : "2450.0",
  "COMM" : "",
  "DEPTNO" : "10"
}, {
  "EMPNO" : "7788",
  "ENAME" : "SCOTT",
  "JOB" : "ANALYST",
  "MGR" : "7566",
  "HIREDATE" : "Sun Apr 19 05:00:00 BST 1987",
  "SAL" : "3000.0",
  "COMM" : "",
  "DEPTNO" : "20"
}, {
  "EMPNO" : "7839",
  "ENAME" : "KING",
  "JOB" : "PRESIDENT",
  "MGR" : "",
  "HIREDATE" : "Tue Nov 17 05:00:00 GMT 1981",
  "SAL" : "5000.0",
  "COMM" : "",
  "DEPTNO" : "10"
}, {
  "EMPNO" : "7844",
  "ENAME" : "TURNER",
  "JOB" : "SALESMAN",
  "MGR" : "7698",
  "HIREDATE" : "Tue Sep 08 05:00:00 BST 1981",
  "SAL" : "1500.0",
  "COMM" : "0.0",
  "DEPTNO" : "30"
}, {
  "EMPNO" : "7876",
  "ENAME" : "ADAMS",
  "JOB" : "CLERK",
  "MGR" : "7788",
  "HIREDATE" : "Sat May 23 05:00:00 BST 1987",
  "SAL" : "1100.0",
  "COMM" : "",
  "DEPTNO" : "20"
}, {
  "EMPNO" : "7900",
  "ENAME" : "JAMES",
  "JOB" : "CLERK",
  "MGR" : "7698",
  "HIREDATE" : "Thu Dec 03 05:00:00 GMT 1981",
  "SAL" : "950.0",
  "COMM" : "",
  "DEPTNO" : "30"
}, {
  "EMPNO" : "7902",
  "ENAME" : "FORD",
  "JOB" : "ANALYST",
  "MGR" : "7566",
  "HIREDATE" : "Thu Dec 03 05:00:00 GMT 1981",
  "SAL" : "3000.0",
  "COMM" : "",
  "DEPTNO" : "20"
}, {
  "EMPNO" : "7934",
  "ENAME" : "MILLER",
  "JOB" : "CLERK",
  "MGR" : "7782",
  "HIREDATE" : "Sat Jan 23 05:00:00 GMT 1982",
  "SAL" : "1300.0",
  "COMM" : "",
  "DEPTNO" : "10"
} ]

        final JXPathContext jxp = JXPathContext.newContext(employeeList);

        assertEquals(14, jxp.selectNodes("EMPNO").size());
        assertEquals(14, jxp.selectNodes("//EMPNO").size());
        assertEquals(4, jxp.selectNodes("/.[*]/EMPNO").size()); // should be 14
        assertEquals(14, jxp.selectNodes("/EMPNO").size());
        assertEquals(0, jxp.selectNodes("/*/EMPNO").size()); // should also be 14

Here we notice that the last result is wrong again as well... but the index based one is wrong as well. And it seems like it's only returning entries where all map values where non-empty.

Not sure if there's something I'm not getting, but it looks like something isn't quite right here.

Issue Links

• relates to: JXPATH-168 Iterator on JSON skips nodes that have a "false" property