I need your help on extract column names and values in the trigger augment method.
Table Def :
create table dy_data (
id timeuuid,
data_key text,
time timestamp,
data text,primary key((id,data_key),time)
) with clustering order by (time desc);
Trigger Code :
public class ArchiveTrigger implements ITrigger {
public Collection<RowMutation> augment(ByteBuffer key, ColumnFamily cf) {
try {
// Below loop only has 2 columns ( one is "data" and another one may be "time" but i am not sure, because i cannot get value.
for (Column cell : cf) {
//Got Exception if I try to get column name
String name = ByteBufferUtil.string(cell.name());
//Got only "data" column value and empty value for another column may be "time". If I try ByteBufferUtil.toLong(cell.value()) it throws exception
String value = ByteBufferUtil.string(cell.value());
log(" name = " + name);
log(" value = " + value);
}
} catch (Exception e) {
logger.warn("Exception ", e);
}
return null;
}
}
I tried my best to search sample code in google. But failed. Please help me with sample code. Thanks in advance.
Thanks iamaleksey for you help. Your replies helps me a lot.
Below are the code snippet which will be useful for trigger users,
public Collection<RowMutation> augment(ByteBuffer key, ColumnFamily cf) {
try {
ByteBuffer id_bb = CompositeType.extractComponent(key, 0);
UUID id=TimeUUIDType.instance.compose(id_bb);
ByteBuffer data_key_bb = CompositeType.extractComponent(key, 1);
String data_key=UTF8Type.instance.compose(data_key_bb);
Iterator col_itr=cf.iterator();
Column ts_col=(Column)col_itr.next();
ByteBuffer time_bb=CompositeType.extractComponent(ts_col.name(),0);
long time=(TimestampType.instance.compose(time_bb)).getTime();
Column data_bb=(Column)col_itr.next();
String data=UTF8Type.instance.compose(data_bb.value());
log(" id --> "+id.toString());
log(" data_key-->"+data_key);
log(" time == "+time);
log(" data == "+data);
} catch (Exception e) {
logger.warn("Exception ", e);
}
return null;
}
PS: Since I know my table format, I hardcoded the column comparator type. If we want to write generic trigger code, we can use cf.getComponentComparator()/getKeyValidator().
To get 'id' and 'data_key' you'll have to split the key (ByteBuffer key, the first argument to augment). 'time' will be in the first part of cell.name() - you'd still need to split it. 'data' will be the cell.value(), no need to do any splitting.
Related
I try to get patient information, by sending an ID to the server. I expect the result to be a JSONObject, as only one patient corresponds with the ID. However, what i get is a JSONArray. I have tried to do getJSONObject(0), but it gives this error:
Index 0 out of range [0..0)
Why i is an Array and not an Object, and how do i deal with it?
This is my java code in the activity:
new HttpRequestTask(
"getPatientFull",
new String[]{"ID"},
new String[]{PatientID}, new HttpRequestTask.ResultReceiver() {
#Override
public void processResult(String apiFunctionName, JSONObject result) {
if (result != null) {
try {
if (result.has("error")) {
shorttoast("ERROR: " + result.getString("error") + "saving patient file");
} else {
if (result.has("patient_details")) {
patientName = result.getJSONArray("patient_details").getJSONObject(0).getString("NAME");
shorttoast(patientName);
}
}
} catch (JSONException ex) {
shorttoast("ERROR" + ex.getLocalizedMessage());
}
} else
shorttoast("Retreiving failed");
}
}).execute();
The PatientID is defined earlier in the code (it's an existing patient id).
and this is the php API function that was defined by my teacher:
app.post("/getPatientFull", function (req, res) {
pool.getConnection(function (err, connection) {
connection.query('SELECT * FROM PatientDossier WHERE PATIENT_ID=?',
[req.query.ID],
function (error, results, fields) {
if (error) {
res.status(403).json({"error": error.code});
} else {
res.status(200).json({patient_details:results});
}
});
connection.release();
});
});
The PHP function does not return a single object, it returns an array.
So, you should expect a JSONArray on the Android side.
As to why getJSONObject(0) is giving you an out-of-bounds error, I'm not sure.
Try using the debugger to look at the JSONArray, and see what's in it. It's possible that you searched for a patient id that's not in the database, and the PHP code returned an empty array. Your code should be checking that anyway.
It also looks like maybe "result" is a JSONObject containing the array, under the key "patient_details", in which case, you need to get the value of "patient_details" and index into that array. If you show us the JSON response, it would be easier to tell.
I'm using Dynamicloud and something is wrong in my code:
This is my code:
RecordModel contactFormModel = new RecordModel(contactModelId);
RecordModel userFormModel = new RecordModel(userContactModelId);
DynamicProvider<ContactForm> provider = new DynamicProviderImpl<ContactForm>(new RecordCredential(csk, aci));
contactFormModel.setBoundClass(ContactForm.class);
Query<ContactForm> query = provider.createQuery(contactFormModel);
query.setAlias("contact");
query.setProjection("contact.namef, contact.comments");
JoinClause join = Conditions.innerJoin(userFormModel, "user", "contact.id = user.contactid");
query.join(join);
try {
RecordResults<ContactForm> list = query.add(Conditions.like("contact.namef", "ProBusiness%")).list();
System.out.println("list = " + list.getFastReturnedSize());
if (list.getFastReturnedSize() > 0) {
System.out.println("Contact Name = " + list.getRecords().get(0).getName());
System.out.println("Contact Comments = " + list.getRecords().get(0).getComments());
}
} catch (DynamicloudProviderException e) {
e.printStackTrace();
}
This code throws the following Exception:
org.dynamicloud.exception.DynamicloudProviderException: Invalid statement. Please check aliases, field identifiers, projections and query conditions.
What's wrong?
Thanks!
Hi
The problems is the missing "id" in your projection section. You need to set the id of one model involved in your JoinClause.
Dynamicloud always order the results by Id, in this case the query has ambiguous columns user.id and contact.id"
Try to put the following id in your projection (of course depends of your needs):
query.setProjection("contact.id, contact.namef, contact.comments");
Hope this helps!
I am working with Jackcess to read and categorize an access database. It's simply meant to open the database, loop through each line, and print out individual row data to the console which meet certain conditions. It works fine, except for when I try to read numeric values. My code is below. (This code is built into a Swing GUI and gets executed when a jbutton is pressed.)
if (inv == null) { // Check to see if inventory file has been set. If not, then set it to the default reference path.
inv = rPath;
}
if (inventoryFile.exists()) { // Check to see if the reference path exists.
List<String> testTypes = jList1.getSelectedValuesList();
List<String> evalTypes = jList3.getSelectedValuesList();
List<String> grainTypes = jList2.getSelectedValuesList();
StringBuilder sb = new StringBuilder();
for (int i=0; i<=evalTypes.size()-1; i++) {
if (i<evalTypes.size()-1) {
sb.append(evalTypes.get(i)).append(" ");
}
else {
sb.append(evalTypes.get(i));
}
}
String evalType = sb.toString();
try (Database db = DatabaseBuilder.open(new File(inv));) {
Table sampleList = db.getTable("NTEP SAMPLES LIST");
Cursor cursor = CursorBuilder.createCursor(sampleList);
for (int i=0; i<=testTypes.size()-1; i++) {
if ("Sample Volume".equals(testTypes.get(i))) {
if (grainTypes.size() == 1 && "HRW".equals(grainTypes.get(0))) {
switch (evalType) {
case "GMM":
for (Row row : sampleList){
if (null != row.getString("CURRENTGAC")) {}
if ("HRW".equals(row.get("GRAIN")) && row.getDouble("CURRENTGAC")>=12.00) {
System.out.print(row.get("GRAIN") + "\t");
System.out.println(row.get("CURRENTGAC"));
}
}
break;
case "NIRT":
// some conditional code
break;
case "TW":
// some more code
break;
}
}
else {
JOptionPane.showMessageDialog(null, "Only HRW samples can be used for the selected test(s).", "Error", JOptionPane.ERROR_MESSAGE);
}
break;
}
}
}
catch (IOException ex) {
Logger.getLogger(SampleFilterGUI.class.getName()).log(Level.SEVERE, null, ex);
}
When the code is run I get the following error:
java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Double
The following condition looks to be what is throwing the error.
row.getDouble("CURRENTGAC")>=12.00
It appears that when the data is read from the database, the program is reading everything as a string, even though some fields are numeric. I was attempting to cast this field as a double, but java doesn't seem to like that. I have tried using the Double.parseDouble() and Double.valueOf() commands to try converting the value (as mentioned here) but without success.
My question is, how can I convert these fields to numeric values? Is trying to type cast the way to go, or is there a different method I'm not aware of? You will also notice in the code that I created a cursor, but am not using it. The original plan was to use it for navigating through the database, but I found some example code from the jackcess webpage and decided to use that instead. Not sure if that was the right move or not, but it seemed like a simpler solution. Any help is much appreciated. Thanks.
EDIT:
To ensure the program was reading a string value from my database, I input the following code
row.get("CURRENTGAC").getClass().getName()
The output was java.lang.String, so this confirms that it is a string. As was suggested, I changed the following code
case "GMM":
for (Row row : sampleList){
if (null != row.get("CURRENTGAC"))
//System.out.println(row.get("CURRENTGAC").getClass().getName());
System.out.println(String.format("|%s|", row.getString("CURRENTGAC")));
/*if ("HRW".equals(row.get("GRAIN")) && row.getDouble("CURRENTGAC")>=12.00 && row.getDouble("CURRENTGAC")<=14.00) {
System.out.print(row.get("GRAIN") + "\t");
System.out.println(row.get("CURRENTGAC"));
}*/
}
break;
The ouput to the console from these changes is below
|9.85|
|11.76|
|9.57|
|12.98|
|10.43|
|13.08|
|10.53|
|11.46|
...
This output, although looks numeric, is still of the string type. So when I tried to run it with my conditional statement (which is commented out in the updated sample code) I still get the same java.lang.ClassCastException error that I was getting before.
Jackcess does not return all values as strings. It will retrieve the fields (columns) of a table as the appropriate Java type for that Access field type. For example, with a test table named "Table1" ...
ID DoubleField TextField
-- ----------- ---------
1 1.23 4.56
... the following Java code ...
Table t = db.getTable("Table1");
for (Row r : t) {
Object o;
Double d;
String fieldName;
fieldName = "DoubleField";
o = r.get(fieldName);
System.out.println(String.format(
"%s comes back as: %s",
fieldName,
o.getClass().getName()));
System.out.println(String.format(
"Value: %f",
o));
System.out.println();
fieldName = "TextField";
o = r.get(fieldName);
System.out.println(String.format(
"%s comes back as: %s",
fieldName,
o.getClass().getName()));
System.out.println(String.format(
"Value: %s",
o));
try {
d = r.getDouble(fieldName);
} catch (Exception x) {
System.out.println(String.format(
"r.getDouble(\"%s\") failed - %s: %s",
fieldName,
x.getClass().getName(),
x.getMessage()));
}
try {
d = Double.parseDouble(r.getString(fieldName));
System.out.println(String.format(
"Double.parseDouble(r.getString(\"%s\")) succeeded. Value: %f",
fieldName,
d));
} catch (Exception x) {
System.out.println(String.format(
"Double.parseDouble(r.getString(\"%s\")) failed: %s",
fieldName,
x.getClass().getName()));
}
System.out.println();
}
... produces:
DoubleField comes back as: java.lang.Double
Value: 1.230000
TextField comes back as: java.lang.String
Value: 4.56
r.getDouble("TextField") failed - java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Double
Double.parseDouble(r.getString("TextField")) succeeded. Value: 4.560000
If you are unable to get Double.parseDouble() to parse the string values from your database then either
they contain "funny characters" that are not apparent from the samples you posted, or
you're doing it wrong.
Additional information re: your sample file
Jackcess is returning CURRENTGAC as String because it is a Text field in the table:
The following Java code ...
Table t = db.getTable("NTEP SAMPLES LIST");
int countNotNull = 0;
int countAtLeast12 = 0;
for (Row r : t) {
String s = r.getString("CURRENTGAC");
if (s != null) {
countNotNull++;
Double d = Double.parseDouble(s);
if (d >= 12.00) {
countAtLeast12++;
}
}
}
System.out.println(String.format(
"Scan complete. Found %d non-null CURRENTGAC values, %d of which were >= 12.00.",
countNotNull,
countAtLeast12));
... produces ...
Scan complete. Found 100 non-null CURRENTGAC values, 62 of which were >= 12.00.
Hey guys I was looking through parse.com examples and documentation but haven't been able to figure out how to change the value of something that's stored in a column in a parse class(specifically a string that's a number e.g., Column name:ExampleColumn - string - 5) . For example I want to do something like this when a button is clicked
#Override
public void onClick(View arg0) {
ParseQuery<ParseObject> query = new ParseQuery<ParseObject> ("ExampleClass");
ExampleColumn = ExampleColumn + 1; /* obviously this won't work but it shows exactly what i want to do with the column, so that this would make ExampleColumn = 6 */
}
With Parse, you don't work directly with columns. You work with objects. So, if you want to change the value of "a column", you need to
fetch the object (row) you want to change
edit the property on that object
save the object again.
If the column data type is string you have to convert to integer before increment it.
ParseQuery query = new ParseQuery ("ExampleClass");
query.whereEqualTo("objectId",your_object_id);
query.getFirstInBackground(new GetCallback<ParseObject>() {
public void done(ParseObject object, ParseException e) {
if (object == null) {
Log.d("score", "The getFirst request failed.");
} else {
int val=Integer.parseInt(object.getString("exampleColumn"));
val++;
object.put("exampleColumn",val);
object.saveInBackground();
}
}
});
In my Java code I have embedded a SQL query which fetches data from a database and stores it in a result-set. I want to add a function or a piece of code which will take only non-negative data from the result-set for further processing.
Assumption: The result set can contain positive/negative/zero data values as well as characters. Also i cannot change the SQL query as its out of my scope.
try something like this, i think it will do the job
private ArrayList getNegativeNumbers(ResultSet rs, String coulumnName ) throws SQLException
{
ArrayList ret = new ArrayList();
while(rs.next()){
try {
int x = rs.getInt(coulumnName);
if(x>=0){
ret.add(new Integer(x));
}
} catch (Exception ex) {
String x = rs.getString(coulumnName);
ret.add(x);
}
}
return ret;
}
UPDATED 2. Sorry for my edits, i missread the question
while (resultSet.next()) {
if(resultSet.getInt("Column name") > 0);
Processmethod(resultSet.getInt("Column name") );
}