add items to complicated data-struc `Map<String, Map<String,String>>` [closed] - java

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I have the following complex data-structure:
Map<String, Map<String,String>> URL_and_entities = new HashMap<String, Map<String,String>>();
on the inside of a loop I finally want to populate it but I can't figure out how.
This is my code, it's essentially a series of nested loops that make an HTTP request to determine if they share a relationship, which is revealed by the presence (or absence) of a url. I'm trying to save the URL (if it exists), and the two entities that evoked it:
for (String entity_1 : Q_value_references_for_sentence_entities)
{
for (String entity_2 : Q_value_references_for_sentence_entities)
{
String URL_czech = "http://milenio.dcc.uchile.cl/sparql?default-graph-uri=&query=PREFIX+%3A+%3Chttp%3A%2F%2Fwww.wikidata.org%2Fentity%2F%3E%0D%0ASELECT+*+WHERE+%7B%0D%0A+++%3A"
+ entity_1 + "+%3FsimpleProperty+%3A"
+ entity_2 + "%0D%0A%7D%0D%0A&format=text%2Fhtml&timeout=0&debug=on";
URL wikidata_page = new URL(URL_czech);
HttpURLConnection wiki_connection = (HttpURLConnection)wikidata_page.openConnection();
InputStream wikiInputStream = null;
try
{
// try to connect and use the input stream
wiki_connection.connect();
wikiInputStream = wiki_connection.getInputStream();
}
catch(IOException error)
{
// failed, try using the error stream
wikiInputStream = wiki_connection.getErrorStream();
}
// parse the input stream using Jsoup
Document docx = Jsoup.parse(wikiInputStream, null, wikidata_page.getProtocol()+"://"+wikidata_page.getHost()+"/");
Elements link_text = docx.select("table.sparql > tbody > tr:nth-child(2) > td > a");
//link_text.text();
for (Element l : link_text)
{
String output = l.text();
output = output.substring(0, output.length()-1);
list_of_relation_URLs.add( output );
URL_and_entities.put( output , (entity_1, entity_2));
}
}
}
I'm not oppoed to using that crazy google library of wonky data-strucs, I've used it before, but in this case I can't see a compelling reason why it would be any better than Map<String, Map<String,String>>
Update
I'm having trouble getting the values out. This doesn't work it seems
String first__english_lang_Q = retrieved_entities.getKey();
String second_english_lang_Q = retrieved_entities.getValue();
System.out.println("`(" + value + ")'" + "`( " + entity_1 + ", " + entity_2 + ")'");

You just need a tuple, You can use the apache common Pair
Map<String, Pair<String,String>> URL_and_entities = new HashMap<String, Pair<String,String>>();
URL_and_entities.put("something", Pair.of("left", "right"))
URL_and_entities.get("something").getLeft();
URL_and_entities.get("something").getRight();

Try this:
Map<String,String> entities;
for (String entity_1 : Q_value_references_for_sentence_entities)
{
for (String entity_2 : Q_value_references_for_sentence_entities)
{
entities = new HashMap<String, String>();
entities.put(entity_1, entity_2);
...check that URL exist and doesn't return null, and then convert it to a String...
URL_and_entities.put(output, entities);
}
}
}
I don't understand though, why you are using a Map to store the two entities. Unless you plan on using one entity to reference the second entity, you can simply store the two entities in a simple array (or technically even an ArrayList or HashSet would be better than a Map).
Just do:
Map<String, String[]> URL_and_entities = new HashMap<String, String[]>();
String [] entities = new String[2];
for (String entity_1 : Q_value_references_for_sentence_entities)
{
for (String entity_2 : Q_value_references_for_sentence_entities)
{
entities[0] = entity_1;
entities[1] = entity_2;
...check that URL exist and doesn't return null, and then convert it to a String...
URL_and_entities.put(output, entities);
}
}
}
Then to retrieve and print all the values in the set you just do:
for (String url: byLetter.keySet()) {
String [] retrievedValues = URL_and_entities.get(url);
System.out.println(url + " " + retrievedValues[0] + ", " + retrievedValues[1];
}
If using an ArrayList do:
for (String url: byLetter.keySet()) {
ArrayList retrievedValues = URL_and_entities.get(url);
System.out.println(url + " " + retrievedValues.get(0) + ", " + retrievedValues.get(1);
}

Related

Appending SQL data into datatables using JAVA in JSP

In my SQL Server I have the following result sets after all the condition filtering and sum query execution.
I would like to be shown like this in my page (refer to the screenshot below).
I have tried the below JAVA code that gave me the results that I appended into my datatables.
<%
ArrayList<String[]> rows = sqlq.querySQL();
String rowsetdate = new String();
String rowres1 = new String();
for(String[] rowset : rows) {
rowsetdate = rowset[0];
rowres1 = rowres1 + rowset[1]+ ",";
for(String rowres2 : rowset) {
rowres1 = rowres1 + rowres2 + ",";
}
rowres1 = rowres1.substring(0, rowres1.length()-1);
rowres1 = rowres1 + "|";
}
rowres1 = rowres1.substring(0, rowres1.length()-1);
%>
<tr>
<td><%if (rowres1 == null) out.print(""); else out.print(rowres1);%></td>
</tr>
sqlq.querySQL() is used to send my SQL query to JDBC in order for me to send query to my DB.
Photo below is the appended data in my datatables after the code execution, on the left is the Date and on the right is the data.
I tried some different code,
<%
ArrayList<String[]> rows = sqlq.querySQL();
for(String[] rowset : rows) {
<tr>
<td><%if (rowset[0] == null) out.print(""); else out.print(rowset[0]);%></td>
<td><%if (rowset[1] == null) out.print(""); else out.print(rowset[1]);%></td>
</tr>
}
%>
which did not achieve my expected results also, it returns the data like how I see it in my SSMS (check screenshot below)
What did I do wrong and how should I do it to get my expected outcome? (screenshot below)
Appreciate the help from all of you.
You can use a Map that its key is date and its value again is a Map. Inner Map uses trans as key and sumtot as value.
Map<String, Map<String, String>> mapByDate = new HashMap<>();
TreeSet<String> allTrans = new TreeSet<>();
for (String[] row : rows) {
Map<String, String> mapByDateAndTrans = mapByDate.get(row[0]);
if (mapByDateAndTrans == null) {
mapByDateAndTrans = new HashMap<>();
}
mapByDateAndTrans.put(row[1], row[2]);
mapByDate.put(row[0], mapByDateAndTrans);
allTrans.add(row[1]);
}
Here is a sample code to print data as you might expect:
System.out.println("Date/Trans: " + allTrans);
for (Map.Entry<String, Map<String, String>> mapByDateEntry : mapByDate.entrySet()) {
System.out.print(mapByDateEntry.getKey() + ": ");
Map<String, String> mapByTrans = mapByDateEntry.getValue();
for (String trans : allTrans) {
String sumtot = mapByTrans.get(trans);
if (sumtot != null) {
System.out.print("[ " + sumtot + " ]");
} else {
System.out.print("[ ]");
}
}
System.out.println();
}
The output:
Date/Trans: [11200, 11201, 11202]
2019-07-02: [ 136 ][ 18 ][ 14 ]
2019-07-03: [ 164 ][ 10 ][ 8 ]
Or we can generate an HTML table content:
StringBuilder tableBuilder = new StringBuilder("<table border = 1>");
// table header
tableBuilder.append("<tr>");
tableBuilder.append("<th>date/trans</th>");
for (String trans : allTrans) {
tableBuilder.append("<th>").append(trans).append("</th>");
}
tableBuilder.append("</tr>");
// table rows
for (Map.Entry<String, Map<String, String>> mapByDateEntry : mapByDate.entrySet()) {
tableBuilder.append("<tr>");
tableBuilder.append("<td>").append(mapByDateEntry.getKey()).append("</td>");
Map<String, String> mapByTrans = mapByDateEntry.getValue();
for (String trans : allTrans) {
String sumtot = mapByTrans.get(trans);
if (sumtot != null) {
tableBuilder.append("<td>").append(sumtot).append("</td>");
} else {
tableBuilder.append("<td></td>");
}
}
tableBuilder.append("<tr>");
}
tableBuilder.append("</table>");
System.out.println(tableBuilder.toString());
The Output:
<table border = 1><tr><th>date/trans</th><th>11200</th><th>11201</th><th>11202</th></tr><tr><td>2019-07-02</td><td>136</td><td>18</td><td>14</td><tr><tr><td>2019-07-03</td><td>164</td><td>10</td><td>8</td><tr></table>
If we save generated output as an HTML file, It maybe your desired result (screenshot below). Also you can change the code to be used in JSP:
To have an ordered Map by natural order of its keys, a TreeMap can be used. So to print the data ordered by date, we can construct a new TreeMap containing the mapByDate data:
TreeMap<String, Map<String, String>> sortedMapByDate = new TreeMap<>(mapByDate);
// table rows
for (Map.Entry<String, Map<String, String>> mapByDateEntry : sortedMapByDate.entrySet()) {
tableBuilder.append("<tr>");
tableBuilder.append("<td>").append(mapByDateEntry.getKey()).append("</td>");
Map<String, String> mapByTrans = mapByDateEntry.getValue();
for (String trans : allTrans) {
String sumtot = mapByTrans.get(trans);
if (sumtot != null) {
tableBuilder.append("<td>").append(sumtot).append("</td>");
} else {
tableBuilder.append("<td></td>");
}
}
tableBuilder.append("<tr>");
}
It's wasteful to do this in Java code, that's what the window functions are for in SQL. If you have a query like SELECT datet, trans, sumtout FROM ... you can use SUM with OVER:
SELECT DISTINCT datet, SUM(sumtout) OVER (PARTITION BY datet)
FROM ...
ORDER BY datet;

Alfresco, query with dynamic values

I have a Map with different values:
props = new HashMap<String, Object>();
props.put("cmis:objectTypeId", "D:ruc:PLICO");
props.put("cmis:name", "PLICO_1.pdf");
props.put("cmis:description", "Descr");
props.put("ruc:doc_surname", "Rossi");
props.put("ruc:doc_name", "Mario");
I want to do a query (QueryStatement or other) that dynamically reads this parameters (some of them can be missing) and build QueryStatement.
Does it exist an easy way to generate the query String for QueryStatement? Or do I should iterate my Map to build a String containing all the parameters and values in my query?
My solution, but maybe somebody know how to improve it without dynamically build the query string:
StringBuilder query = new StringBuilder("SELECT * FROM ? where ");
String folder = null;
if (path!=null)
{
folder = findPath(path);
if (folder==null)
{
return null;
}
query.append("IN_FOLDER(?) AND ");
}
ArrayList <String> values = new ArrayList<String>();
Map<String, Object> properties = loadAnnotationAndData(doc);
String objectType = properties.remove(MyEnum.cmis_object_type_id.getValue()).toString();
for (Map.Entry<String, Object> entry : properties.entrySet())
{
System.out.println(entry.getKey() + " - " + entry.getValue());
query.append(entry.getKey() + "=? AND ");
values.add(entry.getValue().toString());
}
query.delete(query.length()-4, query.length());
query.append(" ORDER BY cmis:creationDate");
System.out.println(query.toString());
Session cmisSession = getCmisSession();
QueryStatement qs=
cmisSession.createQueryStatement(query.toString());
int offset = 1;
qs.setType(offset++, objectType);
if (path!=null)
{
qs.setString(offset++, folder);
}
for (int i=0; i<values.size(); i++)
{
System.out.println(values.get(i).toString());
qs.setString(i+offset, values.get(i).toString());
}

Create Custom InputFormat of ColumnFamilyInputFormat for cassandra

I am working on a project, using cassandra 1.2, hadoop 1.2
I have created my normal cassandra mapper and reducer, but I want to create my own Input format class, which will read the records from cassandra, and I'll get the desired column's value, by splitting that value using splitting and indexing ,
so, I planned to create custom Format class. but I'm confused and not able to know, how would I make it? What classes are to be extend and implement, and how I will able to fetch the row key, column name, columns value etc.
I have my Mapperclass as follow:
public class MyMapper extends
Mapper<ByteBuffer, SortedMap<ByteBuffer, IColumn>, Text, Text> {
private Text word = new Text();
MyJDBC db = new MyJDBC();
public void map(ByteBuffer key, SortedMap<ByteBuffer, IColumn> columns,
Context context) throws IOException, InterruptedException {
long std_id = Long.parseLong(ByteBufferUtil.string(key));
long newSavePoint = 0;
if (columns.values().isEmpty()) {
System.out.println("EMPTY ITERATOR");
sb.append("column_N/A" + ":" + "N/A" + " , ");
} else {
for (IColumn cell : columns.values()) {
name = ByteBufferUtil.string(cell.name());
String value = null;
if (name.contains("int")) {
value = String.valueOf(ByteBufferUtil.toInt(cell.value()));
} else {
value = ByteBufferUtil.string(cell.value());
}
String[] data = value.toString().split(",");
// if (data[0].equalsIgnoreCase("login")) {
Long[] dif = getDateDiffe(d1, d2);
// logics i want to perform inside my custominput class , rather here, i just want a simple mapper class
if (condition1 && condition2) {
myhits++;
sb.append(":\t " + data[0] + " " + data[2] + " "+ data[1] /* + " " + data[3] */+ "\n");
newSavePoint = d2;
}
}
sb.append("~" + like + "~" + newSavePoint + "~");
word.set(sb.toString().replace("\t", ""));
}
db.setInterval(Long.parseLong(ByteBufferUtil.string(key)), newSavePoint);
db.setHits(Long.parseLong(ByteBufferUtil.string(key)), like + "");
context.write(new Text(ByteBufferUtil.string(key)), word);
}
I want to decrease my Mapper Class logics, and want to perform same calculations on my custom input class.
Please help, i wish for the positive r4esponse from stackies...
You can do the intended task by moving the Mapper logic to your custom input class (as you have indicated already)
I found this nice post which explains a similar problem statement as you have. I think it might solve your problem.

Java: Get properties of an object by parsing XML-file

I got a question regarding XML and parsing it. I use JDOM to parse my XML-File, but I got a little Problem.
A sample of my XML-File looks like this:
<IO name="Bus" type="Class">
<ResourceAttribute name="Bandwidth" type="KiloBitPerSecond" value="50" />
</IO>
Bus is a object instance of the class IO. The object got the name and type properties. Additional it has some attributes, like in the sample, the Attribute Bandwidth with the value of 50 and the datatype KiloBitPerSecond.
So when I want to loop over the file with:
for(Element packages : listPackages)
{
Map<String, Values> valueMap = new HashMap<String, Values>();
List<Element> objectInstanceList = packages.getChildren();
for(Element objects : objectInstanceList)
{
List<Element> listObjectClasses = objects.getChildren();
for(Element classes : listObjectClasses)
{
List<Element> listObjectAttributes = classes.getChildren();
for(Element objectAttributes : listObjectAttributes)
{
List<Attribute> listAttributes = objectAttributes.getAttributes();
for(Attribute attributes : listAttributes)
{
String name = attributes.getName();
String value = attributes.getValue();
AttributeType datatype = attributes.getAttributeType();
Values v = new Values(name, datatype, value);
valueMap.put(classes.getName(), v);
System.out.println(name + ":" + value);
}
}
}
}
//System.out.println(valueMap);
}
values is a class which defines the object attribute:
public class Values{
private String name;
//private AttributeType datatype;
private String value;
Thats the rest of the Code. I got two question relating that. The first one got more priority at the moment.
How do I get the values of the object(Attribute.Name = Bandwidth; Attribute.Value = 50) ? Istead that I get
name:Bus
type:Class
I thought about an additional for-loop, but the JDOM class attribute dont have a method called getAttributes().
Thats just second priority because without question 1 I cannot go further. As you see in the sample, an Attribute got 3 properties, name, type and value. How can I extract that triple put of the sample. JDOM seems just to know 2 properties for an Attribute, name and value.
thanks a lot in advance and hopefully I managed to express my self.
Edit: Added an additional for-loop in it, so the output now is:
name:Bandwidth
type:KiloBitPerSecond
value:50
That means name is the name of that property and value is the value of name. Didnt know that. At least question one is clearer now and I can try working on 2, but the new information makes 2 clearer to me.
In xml the opening tag of elements are encosoed between < and > (or />) , after the < comes the name of the element, then comes a list of attributes in the format name="value". An element can be closed inline with /> or with a closing tag </[element name]>
It would be preferable to use recursion to parse your xml instead of badly readable/maintainable nested for loops.
Here is how it could look like:
#Test
public void parseXmlRec() throws JDOMException, IOException {
String xml = "<root>"
+ "<Package>"
+ "<IO name=\"Bus\" type=\"Class\">\r\n" +
" <ResourceAttribute name=\"Bandwidth\" type=\"KiloBitPerSecond\" value=\"50\" />\r\n" +
" </IO>"
+ "</Package>"
+ "</root>";
InputStream is = new ByteArrayInputStream(xml.getBytes());
SAXBuilder sb = new SAXBuilder();
Document document = sb.build(is);
is.close();
Element root = document.getRootElement();
List<Element> children = root.getChildren();
for(Element element : children) {
parseelement(element);
}
}
private void parseelement(Element element) {
System.out.println("Element:" + element.getName());
String name = element.getAttributeValue("name");
if(name != null) {
System.out.println("name: " + name);
}
String type = element.getAttributeValue("type");
if(type != null) {
System.out.println("type: " + type);
}
String value = element.getAttributeValue("value");
if(value != null) {
System.out.println("value: " + value);
}
List<Element> children = element.getChildren();
if(children != null) {
for(Element child : children) {
parseelement(child);
}
}
}
This outputs:
Element: Package
Element: IO
name: Bus
type: Class
Element: ResourceAttribute
name: Bandwidth
type: KiloBitPerSecond
value: 50
While parsing, check the name of each element and instanciate the coresponding objects. For that I would suggest to write a separate method to handle each element. For example:
void parsePackage(Element packageElement) { ... }
parseIO(Element ioElement) { ... }
void parseResourceAttribute(Element resourceAttributeElement) { ... }

Dynamic data store for ExtJS chart

I am trying to use JSP on server-side to perform a variable number of queries and output the result of all of them as a single block of JSON data for an ExtJS line chart.
The reason the number of queries is variable is because each one represent a different series (a different line) on the line chart, and the number of series is different depending on the line chart that the user selects.
I am using hibernate and my persistence class returns each query data as a: List<Map<String, Object>> (each Map represents one row).
There will always be at least one series (one line on the graph, one query to execute), so the way I was thinking of setting this up is as follows:
1) Have the initial query run and get the first series
2) Run another query to check for any other series that should be on the graph
3) For each "other" series found in the second query run a query that gets the data for that series (same number of rows) and then merge that data into the first List<Map<String, Object>> that was returned in #1 as another column. The query is set-up to order it properly it just needs to be merged at the same index level.
4) Output that List as JSON.
My problem is with #3, I am not sure how to go about the merging the data.
Here's what I have so far:
GenericSelectCommand graphData = new GenericSelectCommand(graphDataQuery);
GenericSelectCommand backSeriesData = new GenericSelectCommand(backSeriesQuery);
List<Map<String, Object>> graphDataList;
List<Map<String, Object>> backSeriesList;
try
{
Persistor myPersistor = new Persistor();
// 1) GET THE INITIAL LINE CHART SERIES
myPersistor.executeTransact(graphData);
graphDataList = graphData.getRows();
// 2) LOOK FOR ANY ADDITIONAL SERIES THAT SHOULD BE ON THE LINE CHART
myPersistor.executeTransact(backSeriesData);
backSeriesList = backSeriesData.getRows();
// 3) FOR EACH ADDITIONAL SERIES FOUND, RUN A QUERY AND APPEND THE DATA TO THE INITIAL LINE CHART SERIES (graphDataList)
for (int i = 0; i < backSeriesList.size(); i++)
{
Map<String, Object> backSeriesBean = backSeriesList.get(i);
// THIS QUERY RETURNS ONE COLUMN OF INT VALUES (THE LINE CHART DATA) WITH THE EXACT SAME NUMBER OF ROWS AS THE INITIAL LINE CHART SERIES (graphDataList)
String backDataQuery = "exec runQuery 'getBackData', '" + backSeriesBean.get("series_id") + "'";
GenericSelectCommand backData = new GenericSelectCommand(backDataQuery);
myPersistor.executeTransact(backData);
List<Map<String, Object>> backDataList = backData.getRows();
// FOR EACH RECORD IN THE BACK DATA (Map<String, Object>)
for (int i = 0; i < backDataList.size(); i++)
{
Map<String, Object> backDataBean = backDataList.get(i);
// HOW DO I ADD IT TO THE RECORD AT THE SAME INDEX LEVEL IN graphDataList (List<Map<String, Object>>)
}
}
}
catch (Throwable e)
{
System.err.println("Error: ");
System.err.println(e.getCause());
}
finally
{
myPersistor.closeSession();
}
// 4) RETURN THE DATA AS JSON NOW THAT IT IS MERGED
for (int i = 0; i < graphDataList.size(); i++)
{
Map<String, Object> graphDataBean = graphDataList.get(i);
out.println(/*JSON FORMAT + graphDataBean.get('data') + JSON FORMAT*/)
}
SOLUTION:
GenericSelectCommand graphData = new GenericSelectCommand(graphDataQuery);
GenericSelectCommand backSeries = new GenericSelectCommand(backSeriesQuery);
List<Map<String, Object>> graphDataList = Collections.emptyList();
List<Map<String, Object>> backSeriesList = Collections.emptyList();
List backDataListArray = new ArrayList();
try
{
// GET THE INITIAL LINE CHART SERIES
Persistor.instance().executeTransact(graphData);
graphDataList = graphData.getRows();
// LOOK FOR ANY ADDITIONAL SERIES THAT SHOULD BE ON THE LINE CHART
Persistor.instance().executeTransact(backSeries);
backSeriesList = backSeries.getRows();
// FOR EACH ADDITIONAL SERIES FOUND, RUN THE QUERY AND ADD IT TO backDataListArray
for (int i = 0; i < backSeriesList.size(); i++)
{
Map<String, Object> backSeriesBean = backSeriesList.get(i);
String backDataQuery = "exec runQuery 'getBackData', " + backSeriesBean.get("series_id");
GenericSelectCommand backData = new GenericSelectCommand(backDataQuery);
Persistor.instance().executeTransact(backData);
List<Map<String, Object>> backDataList = backData.getRows();
backDataListArray.add(backDataList);
}
}
catch (Throwable e)
{
System.err.println("Error: ");
System.err.println(e.getCause());
}
finally
{
Persistor.instance().closeSession();
}
// FOR EACH RECORD IN THE ORIGINAL QUERY, WRITE THE JSON STRING
for (int i = 0; i < graphDataList.size(); i++)
{
StringBuilder backDataString = new StringBuilder();
// BUILD THE BACK DATA STRING (IF THERE IS ANY)
for (int j = 0; j < backDataListArray.size(); j++)
{
List<Map<String, Object>> backDataList = (List<Map<String, Object>>) backDataListArray.get(j);
Map<String, Object> backDataBean = backDataList.get(i);
Map<String, Object> backSeriesBean = backSeriesList.get(j);
backDataString.append(backSeriesBean.get("the_series") + ": " + backDataBean.get("the_count") + ", ");
}
Map<String, Object> graphDataBean = graphDataList.get(i);
out.println("{the_quota: " + graphDataBean.get("the_quota") + ", " + "count_pt_year: " + graphDataBean.get("count_pt_year") + ", " + backDataString + "date_string: '" + graphDataBean.get("date_string") + "'}" + (i + 1 == graphDataList.size() ? "" : "," ));
}
I would not merge the lists. I would just create an outer list for each query and then go through the outer list and return each series list. You can just create the outer list as:
List outerList = new ArrayList();
I would not worry about specifying the types for the outer list as it just makes it more complicated for little benefit.

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