I'm having a little bit trouble with freemarker right now. What I want to do basically in my template: iterate over a list of elements and create for each element a new file.
<#assign x=3>
<#list 1..x as i>
${i}
...create a new file with the output of this loop iteration...
</#list>
I did not find anything about this in the freemarker manual or google. Is there a way to do this?
You can implement this with a custom directive. See freemarker.template.TemplateDirectiveModel, and particularly TemplateDirectiveBody. Custom directives can specify the Writer used in their nested content. So you can do something like <#output file="...">...</#output>, where the nested content will be written into the Writer you have provided in your TemplateDirectiveModel implementation, which in this case should write into the file specified. (FMPP does this too: http://fmpp.sourceforge.net/qtour.html#sect4)
You cannot do this using only FreeMarker. Its idea is to produce the single output stream from your template. It doesn't even care whether you will save the result to file, pass directly to TCP socket, store in the memory as string or do anything else.
If you really want to achieve this, you have to handle file separation by yourself. For example, you can insert special line like:
<#assign x=3>
<#list 1..x as i>
${i}
%%%%File=output${i}.html
...
</#list>
After that you should post-process FreeMarker output by yourself looking for the lines started with %%%%File= and create a new file at this point.
As ddekany said, you can do that implementing a directive. I have coded a little example:
package spikes;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.HashMap;
import java.util.Map;
import freemarker.core.Environment;
import freemarker.template.Configuration;
import freemarker.template.SimpleScalar;
import freemarker.template.Template;
import freemarker.template.TemplateDirectiveBody;
import freemarker.template.TemplateDirectiveModel;
import freemarker.template.TemplateException;
import freemarker.template.TemplateModel;
import io.vertx.core.json.JsonArray;
import io.vertx.core.json.JsonObject;
class OutputDirective implements TemplateDirectiveModel {
#Override
public void execute(
Environment env,
#SuppressWarnings("rawtypes") Map params,
TemplateModel[] loopVars,
TemplateDirectiveBody body)
throws TemplateException, IOException {
SimpleScalar file = (SimpleScalar) params.get("file");
FileWriter fw = new FileWriter(new File(file.getAsString()));
body.render(fw);
fw.flush();
}
}
public class FreemarkerTest {
public static void main(String[] args) throws Exception {
Configuration cfg = new Configuration(Configuration.VERSION_2_3_0);
cfg.setDefaultEncoding("UTF-8");
JsonObject model = new JsonObject()
.put("entities", new JsonArray()
.add(new JsonObject()
.put("name", "Entity1"))
.add(new JsonObject()
.put("name", "Entity2")));
Template template = new Template("Test", "<#assign model = model?eval_json><#list model.entities as entity><#output file=entity.name + \".txt\">This is ${entity.name} entity\n</#output></#list>", cfg);
Map<String, Object> root = new HashMap<String, Object>();
root.put("output", new OutputDirective());
root.put("model", model.encode());
Writer out = new OutputStreamWriter(System.out);
template.process(root, out);
}
}
This will generate two files:
"Entity1.txt": This is Entity1 entity
"Entity2.txt": This is Entity2 entity
:-)
Related
I working on a data mining project using WEKA in Java and the instructions says that I have to create an Attribute object for each attribute in the dataset and add them to a FastVector. I try to look at the API but I don't think I'm doing it right can someone show me the right way to do it. I'm using the iris.arff file
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import weka.core.Attribute;
import weka.core.FastVector;
import weka.core.Instances;
import weka.core.converters.ArffSaver;
public class StartWeka {
public static void main(String[]args)throws Exception{
Instances dataset = new Instances(new BufferedReader(new FileReader("C:/Users/Student/workspace/Data Mining/src/iris.arff.txt")));
Instances train = new Instances(dataset);
train.setClassIndex(train.numAttributes()-1);
System.out.println(dataset.toSummaryString());
Attribute a1 = new Attribute("sepallength", 0);
Attribute a2 = new Attribute("sepalwidth", 1);
Attribute a3 = new Attribute("petalwidth", 2);
FastVector attrs = new FastVector();
attrs.addElement(a1);
}
}
FastVector is deprecated. You can use an ArrayList instead.
If you use an arff file, however, you don't have to do any of that. You can just do the following:
ArffLoader loader = new ArffLoader();
loader.setFile(new File("iris.arff");
Instances structure = loader.getStructure();
structure.setClassIndex(structure.numAttributes() - 1);
From here, you can create a classifier based on your instances. (structure).
I'm using the Jackson set of classes to read in a CSV file, and convert it to xml, but need some advice on how to add a nested value.
The code I'm using is:
package reader;
import java.io.File;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import com.fasterxml.jackson.databind.MappingIterator;
import com.fasterxml.jackson.dataformat.csv.CsvMapper;
import com.fasterxml.jackson.dataformat.csv.CsvSchema;
import com.fasterxml.jackson.dataformat.xml.XmlMapper;
public class Mustang
{
public static void main(String[] args) throws Exception
{
// Define the input file
File input = new File("c:\\temp\\all_idocs.csv");
// Define the output file
File output = new File("c:\\temp\\all_idocs.xml");
System.out.println("INFO: Commencing Conversion");
List<Map<?, ?>> data = readObjectsFromCsv(input); // readObjectsFromCSV(input
// file name)
System.out.println(readObjectsFromCsv(input));
writeAsXml(data, output); // writeAsXml function, to output location
System.out.println("INFO: Conversion Complete");
}
public static List<Map<?, ?>> readObjectsFromCsv(File file)
throws IOException
{
CsvSchema schema = CsvSchema.builder()
.addColumn("A0001")
.addColumn("A0186")
.addColumn("A0187")
.addColumn("A0352")
.addColumn("A0539")
.addColumn("A0963")
.addColumn("A1046")
.addColumn("A0792")
.addColumn("A0218")
.addColumn("A0584")
.addColumn("A0016")
.addColumn("A0017")
.addColumn("A0478")
.addColumn("A0051")
.addColumn("A0052")
.addColumn("A0053")
.addColumn("A0059")
.addColumn("A0440")
.addColumn("A0054")
.addColumn("A0055")
.addColumn("A0056")
.addColumn("A0057")
.addColumn("A0058")
.addColumn("A1128")
.addColumn("A0003")
.addColumn("A0069")
.addColumn("A0070")
.addColumn("A0074")
.addColumn("A0073")
.addColumn("A0071")
.addColumn("A0110")
.addColumn("A0109")
.addColumn("A0108")
.build();
CsvMapper csvMapper = new CsvMapper();
MappingIterator<Map<?, ?>> mappingIterator = csvMapper
.reader(Map.class).with(schema).readValues(file); // Change the "with()" to pull in the schema
return mappingIterator.readAll();
}
public static void writeAsXml(List<Map<?, ?>> data, File file)
throws IOException
{
XmlMapper mapper = new XmlMapper();
mapper.writeValue(file, data);
}
}
If I run this against a CSV file, I get output similar to this:
<item>
<A0001>J1000097</A0001>
<A0186>5028197000004</A0186>
<A0187>1</A0187>
<A0352></A0352>
<A0539>00</A0539>
<A0963>20050209</A0963>
</item>
I want to see if it's possible to indent/nest some of these attributes, to produce something like this:
<item>
<A0001>J1000097</A0001>
<A0186>5028197000004</A0186>
<A0187>
<A0352>12</A0352>
<A0539>00</A0539>
</A0187>
<A0963>20050209</A0963>
</item>
I'm assuming I must have to do something within the builder section of the code, but as I'm new to using it, I can't fathom out how.
In this case you may want to process Map after reading it from CSV, but before writing it as XML. You can then add a wrapper around values you want to group. That is, something like:
Map<?,?> value = ... ; // individual row
Map<String,Object> wrapped = new LinkedHashMap<>();
wrapped.put("A0352", value.remove("A0352"));
wrapped.put("A0539", value.remove("A0539"));
value.put("A0187", wrapped);
another possibility would be to use value conversion between Map, and POJO type that uses #JsonUnwrapped to handle grouping.
Conversion itself may be done using:
MyPOJO value = mapper.convertValue(map, MyPOJO.class); // and/or reverse
but this approach may become more complicated.
I have a code that parses through XML files, edits them and saves them (using dom for this). Now, I have a few files which have the .ftl extension. I have managed to process the ftl file with given answers (using freemarker template configuration) , However, I am unable to save the edited xml back as an FTL.
All of this is in Java. Any suggestions on how I can achieve the saving aspect of the problem?
Again, I want to process, edit and then save an FTL file in Java.
I am appending the code that I have for processing the ftl file.
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import com.google.gson.stream.JsonReader;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;
public class FTLReader {
public static void main(String[] args) {
//Freemarker configuration object
Configuration cfg = new Configuration();
try {
//Load template from source folder
Template template = cfg.getTemplate(filename);
// Build the data-model
Map<String,Object> data = new HashMap<String,Object>();
JsonParser parser = new JsonParser();
//write code to get answers
Object obj = parser.parse(new FileReader("src/answers.txt"));
JsonObject jsonObject = (JsonObject) obj;
data.put("element1", jsonObject.get("element1"));
// Console output
Writer out = new OutputStreamWriter(System.out);
template.process(data, out);
out.flush();
/*write code to edit and save the ftl file
*
*
*
*
* */
// File output (the processed FTL file)
Writer file = new FileWriter (new File("C:\\FTL_helloworld.txt"));
template.process(data, file);
file.flush();
file.close();
} catch (IOException e) {
e.printStackTrace();
} catch (TemplateException e) {
e.printStackTrace();
}
}
}
After reading your question and comments few times, I am probably finally getting to grasp what you are aiming to. So, you have to "patch" the file behind the filename variable from the start of your code (Template template = cfg.getTemplate(filename);). FTL file is basically a text file, so you can process it line by line. Then you must re-initialize your template with the new file content, i.e. do template = cfg.getTemplate(filename); again.
I recently purchased the Book "Programming Google Glass - The Mirror API" By Eric Redmond and in the 2nd chapter we install Freemarker GRE .jar file into the project. There is a part when we have to create a method that renders a template file. I keep getting an error when trying to make a Configuration.
package com.leetinsider.leetfoodfinder;
import java.io.IOException;
import java.io.StringWriter;
import java.util.Map;
import java.util.Random;
import javax.security.auth.login.Configuration;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import com.sun.org.apache.xalan.internal.xsltc.compiler.Template;
public class LeetFoodFinder {
public static String getRandomCuisine()
{
String[] lunchOptions = {
"American", "Chineese", "French", "Italian", "Japenese", "Thai"
};
int choice = new Random().nextInt(lunchOptions.length);
return lunchOptions[choice];
}
public static String render(ServletContext ctx, String template, Map<String, Object> data)
throws IOException, ServletException{
Configuration config = new Configuration();
config.setServletContextForTemplateLoading(ctx, "WEB-INF/views");
config.setDefaultEncoding("UTF-8");
Template ftl = config.getTemplate(template);
try{
//use the data to render the template to the servlet output
StringWriter writer = new StringWriter();
ftl.process(data, writer);
return writer.toString();
}
catch (TemplateException e){
throw new ServletException("Problem while processing template", e);
}
}
}
It tells me that Configuration() cannot be instaniated. Is there an import that I am missing? I put the freemarker-gae2.3.2.0.jar file in the war/WEB-INF/lib directory but am not sure if there is something else I am missing.
Trying to follow along with the book but this is holding me back :/
If you look at your import statement, they're referring to non freemarker classes of the same name.
The jar isn't actually in your build path. Right click the project and choose "Properties", then "Java Build Path". If freemarker isn't in the Libraries list, select Add JARs and find the jar in your project.
Delete the "import javax.security.auth.login.Configuration" line. You need to choose the Freemarker configuration.
Hope that helps.
Hi I am very new to jasper reports. Just have a requirement where i need to retrieve the info from a .jasper file. I am using the below code for that.
But issue is compileReport does not take up the file i have in my local machine and i get a error like
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/digester/Digester
at net.sf.jasperreports.engine.JasperCompileManager.compileReport(JasperCompileManager.java:150)
at jasper.test(jasper.java:28)
at jasper.main(jasper.java:40)
I am not sure what is wrong.Is it not able to get my .jasper file? which class is missing?
I am absolutely clueless.
My code is:
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import dori.jasper.engine.JRException;
import net.sf.jasperreports.engine.JRDataSource;
import net.sf.jasperreports.engine.JasperCompileManager;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.engine.JasperReport;
import net.sf.jasperreports.engine.JasperExportManager;
import net.sf.jasperreports.engine.data.JRBeanCollectionDataSource;
import net.sf.jasperreports.view.JasperViewer;
public class jasper {
public static void test() throws FileNotFoundException, net.sf.jasperreports.engine.JRException{
JasperReport report = JasperCompileManager.compileReport("C:\\Users\\Mandakini\\Downloads\\testReport.jasper");
JasperPrint print = JasperFillManager.fillReport(report, new HashMap<String, String>());
// export it!
//File pdf = File.createTempFile("output.", ".pdf");
OutputStream output= new FileOutputStream(new File("F:/catalog.pdf"));
JasperExportManager.exportReportToPdfStream(print,output);
}
public static void main(String args[]) throws FileNotFoundException, net.sf.jasperreports.engine.JRException{
test();
}
}
Thanks
A java.lang.NoClassDefFoundError or ClassNotFoundException should almost always tell you that the class it references is missing from your classpath. In this case, it's org.apache.commons.digester.Digester. You can download the jar containing this class here.
To produce a report, do something like:
JasperReport jasperReport = (JasperReport) JRLoader.loadObjectFromFile(yourJasperFilePath);
Map<String, Object> parameters = new HashMap<>();
// set your parameters
Class.forName("com.mysql.jdbc.Driver");
Connection con = ...; // possibly get a connection
byte[] report = JasperRunManager.runReportToPdf(jasperReport, parameters, con); // pass the report, the report parameters, and a connection
// this will fill the byte[] with the produced report
FileOutputStream out = new FileOutputStream(somePath);
out.write(report);
out.close();
As to what kind of report it generates, I'm not sure how you set that. That info might be in the .jasper or .jrxml file.