Develop Reference

JUnit test for tess4J application

I want to test my method to see if it will read the file correctly. I just can't seem to wrap my head around JUnit Testing. Can someone show me how to correctly write a JUnit test for this code:
import java.io.File;
import net.sourceforge.tess4j.*;
import net.sourceforge.tess4j.util.LoadLibs;
public class ImageTest {
public static String imageService(String filePath) {
File imageFile = new File("tessImage.png");
ITesseract instance = new Tesseract();
//Let tessdata be extracted in case you dont have tessdata folder
File tessDataFolder = LoadLibs.extractTessResources("tessdata");
//Set the tessdata path
instance.setDatapath(tessDataFolder.getAbsolutePath());
instance.setLanguage("eng");
try {
String result = instance.doOCR(imageFile);
return result;
} catch (TesseractException e) {
System.err.println(e.getMessage());
return "this is an error" ;
}
}
}

Forword: your exception handling is horrific. Don't return an error message when your caller is expecting the OCR string. Stick to the JAVA style. In case of an error - throw an EXCEPTION!
Next: you never actually use the "filePath" parameter. This is clearly a bug.
You first need to ask yourself WHAT to test. Is it the "imageService" method you want to test? Then create a second class and from there, you would test your method. Within this test class, you would take an example file, call your imageService and compare the result with what you would expect. Those kind of comparisons are done with Assert-statements. Please check the jUnit docs for more detail.

Alt-codes only work in Java string when run within Netbeans

I have a small java program that reads a given file with data and converts it to a csv file.
I've been trying to use the arrow symbols: ↑, ↓, → and ← (Alt+24 to 27) but unless the program is run from within Netbeans (Using F6), they will always come out as '?' in the resulting csv file.
I have tried using the unicodes, eg "\u2190" but it makes no difference.
Anyone know why this is happening?
As requested, here is a sample code that gives the same issue. This wont work when run using the .jar file, just creating a csv file containing '?', however running from within Netbeans works.
import java.io.FileNotFoundException;
import java.io.PrintWriter;
public class Sample {
String fileOutName = "testresult.csv";
/**
* #param args the command line arguments
*/
public static void main(String[] args) throws FileNotFoundException {
Sample test = new Sample();
test.saveTheArrow();
}
public void saveTheArrow() {
try (PrintWriter outputStream = new PrintWriter(fileOutName)) {
outputStream.print("←");
outputStream.close();
}
catch (FileNotFoundException e) {
// Do nothing
}
}
}

new PrintWriter(fileOutName) uses the default charset of the JVM - you may have different defaults in Netbeans and in the console.
Google Sheet uses UTF_8 according to this thread so it would make sense to save your file using that character set:
Files.write(Paths.get("testresult.csv"), "←".getBytes(UTF_8));

Using the "<-" character in your editor is for sure not the desired byte 0x27.
Use
outputStream.print( new String( new byte[] { 0x27}, StandardCharsets.US_ASCII);

Google API Translate not working for Language.HINDI

I am attaching the code below.
import com.google.api.translate.Language;
import com.google.api.translate.Translate;
public class Translator {
public static void main(String[] args) {
// Translate trans = new Translate();
try{
System.setProperty("http.proxyHost", "192.16.3.254");
System.setProperty("http.proxyPort", "8080");
Translate.setHttpReferrer("http://code.google.com/p/google-api-translate-java/");
String translatedText = Translate.execute("How are you?", Language.ENGLISH, Language.HINDI);
System.out.println("translated text :" + translatedText);
}catch (Exception e) {
e.printStackTrace();
}
}
}
This is giving output as
translated text : ?? ???? ????
but for Language.FRENCH,Language.SPANISH its giving the translated text.
Could you please tell a solution for this.

If console can not display the chars correctly, it may caused by the Local Setting of the host operation system. If the system local is set to be English, then multi-bytes characters may not be displayed correctly. You can try to write it to a file and check it using a text editor, like Notepad++. And make sure you choose the correct encoding in Notepad++ :)

'Un'-externalize strings from Eclipse or Intellij

I have a bunch of strings in a properties file which i want to 'un-externalize', ie inline into my code.
I see that both Eclipse and Intellij have great support to 'externalize' strings from within code, however do any of them support inlining strings from a properties file back into code?
For example if I have code like -
My.java
System.out.println(myResourceBundle.getString("key"));
My.properties
key=a whole bunch of text
I want my java code to be replaced as -
My.java
System.out.println("a whole bunch of text");

I wrote a simple java program that you can use to do this.
Dexternalize.java
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map.Entry;
import java.util.Properties;
import java.util.Set;
import java.util.Stack;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Deexternalize {
public static final Logger logger = Logger.getLogger(Deexternalize.class.toString());
public static void main(String[] args) throws IOException {
if(args.length != 2) {
System.out.println("Deexternalize props_file java_file_to_create");
return;
}
Properties defaultProps = new Properties();
FileInputStream in = new FileInputStream(args[0]);
defaultProps.load(in);
in.close();
File javaFile = new File(args[1]);
List<String> data = process(defaultProps,javaFile);
buildFile(javaFile,data);
}
public static List<String> process(Properties propsFile, File javaFile) {
List<String> data = new ArrayList<String>();
Set<Entry<Object,Object>> setOfProps = propsFile.entrySet();
int indexOf = javaFile.getName().indexOf(".");
String javaClassName = javaFile.getName().substring(0,indexOf);
data.add("public class " + javaClassName + " {\n");
StringBuilder sb = null;
// for some reason it's adding them in reverse order so putting htem on a stack
Stack<String> aStack = new Stack<String>();
for(Entry<Object,Object> anEntry : setOfProps) {
sb = new StringBuilder("\tpublic static final String ");
sb.append(anEntry.getKey().toString());
sb.append(" = \"");
sb.append(anEntry.getValue().toString());
sb.append("\";\n");
aStack.push(sb.toString());
}
while(!aStack.empty()) {
data.add(aStack.pop());
}
if(sb != null) {
data.add("}");
}
return data;
}
public static final void buildFile(File fileToBuild, List<String> lines) {
BufferedWriter theWriter = null;
try {
// Check to make sure if the file exists already.
if(!fileToBuild.exists()) {
fileToBuild.createNewFile();
}
theWriter = new BufferedWriter(new FileWriter(fileToBuild));
// Write the lines to the file.
for(String theLine : lines) {
// DO NOT ADD windows carriage return.
if(theLine.endsWith("\r\n")){
theWriter.write(theLine.substring(0, theLine.length()-2));
theWriter.write("\n");
} else if(theLine.endsWith("\n")) {
// This case is UNIX format already since we checked for
// the carriage return already.
theWriter.write(theLine);
} else {
theWriter.write(theLine);
theWriter.write("\n");
}
}
} catch(IOException ex) {
logger.log(Level.SEVERE, null, ex);
} finally {
try {
theWriter.close();
} catch(IOException ex) {
logger.log(Level.SEVERE, null, ex);
}
}
}
}
Basically, all you need to do is call this java program with the location of the property file and the name of the java file you want to create that will contain the properties.
For instance this property file:
test.properties
TEST_1=test test test
TEST_2=test 2456
TEST_3=123456
will become:
java_test.java
public class java_test {
public static final String TEST_1 = "test test test";
public static final String TEST_2 = "test 2456";
public static final String TEST_3 = "123456";
}
Hope this is what you need!
EDIT:
I understand what you requested now. You can use my code to do what you want if you sprinkle a bit of regex magic. Lets say you have the java_test file from above. Copy the inlined properties into the file you want to replace the myResourceBundle code with.
For example,
TestFile.java
public class TestFile {
public static final String TEST_1 = "test test test";
public static final String TEST_2 = "test 2456";
public static final String TEST_3 = "123456";
public static void regexTest() {
System.out.println(myResourceBundle.getString("TEST_1"));
System.out.println(myResourceBundle.getString("TEST_1"));
System.out.println(myResourceBundle.getString("TEST_3"));
}
}
Ok, now if you are using eclipse (any modern IDE should be able to do this) go to the Edit Menu -> Find/Replace. In the window, you should see a "Regular Expressions" checkbox, check that. Now input the following text into the Find text area:
myResourceBundle\.getString\(\"(.+)\"\)
And the back reference
\1
into the replace.
Now click "Replace all" and voila! The code should have been inlined to your needs.
Now TestFile.java will become:
TestFile.java
public class TestFile {
public static final String TEST_1 = "test test test";
public static final String TEST_2 = "test 2456";
public static final String TEST_3 = "123456";
public static void regexTest() {
System.out.println(TEST_1);
System.out.println(TEST_1);
System.out.println(TEST_3);
}
}

You may use Eclipse "Externalize Strings" widget. It can also be used for un-externalization. Select required string(s) and press "Internalize" button. If the string was externalized before, it'll be put back and removed from messages.properties file.

May be if you can explain on how you need to do this, then you could get the correct answer.
The Short answer to your question is no, especially in Intellij (I do not know enough about eclipse). Of course the slightly longer but still not very useful answer is to write a plugin. ( That will take a list of property files and read the key and values in a map and then does a regular expression replace of ResourceBundle.getValue("Key") with the value from Map (for the key). I will write this plugin myself, if you can convince me that, there are more people like you, who have this requirement.)
The more elaborate answer is this.
1_ First I will re-factor all the code that performs property file reading to a single class (or module called PropertyFileReader).
2_ I will create a property file reader module, that iterates across all the keys in property file(s) and then stores those information in a map.
4_ I can either create a static map objects with the populated values or create a constant class out of it. Then I will replace the logic in the property file reader module to use a get on the map or static class rather than the property file reading.
5_ Once I am sure that the application performs ok.(By checking if all my Unit Testing passes), then I will remove my property files.
Note: If you are using spring, then there is a easy way to split out all property key-value pairs from a list of property files. Let me know if you use spring.

I would recommend something else: split externalized strings into localizable and non-localizable properties files. It would be probably easier to move some strings to another file than moving it back to source code (which will hurt maintainability by the way).
Of course you can write simple (to some extent) Perl (or whatever) script which will search for calls to resource bundles and introduce constant in this place...
In other words, I haven't heard about de-externalizing mechanism, you need to do it by hand (or write some automated script yourself).

An awesome oneliner from #potong sed 's|^\([^=]*\)=\(.*\)|s#Messages.getString("\1")#"\2"#g|;s/\\/\\\\/g' messages.properties |
sed -i -f - *.java run this inside your src dir, and see the magic.

Indentation issues with Staxmate API

I am using Staxmate API to generate XML file. After reading the tutorial: http://staxmate.codehaus.org/Tutorial I tried making the changes in my code. At last I added the call
doc.setIndentation("\n ", 1, 1);
Which causes the newly generated XML file to be empty! Without this method call entire XML file gets generated as expected.
Suspecting something fishy in in project setup, I created a Test class in the same package with the code given in tutorial:
package ch.synlogic.iaf.export;
import java.io.File;
import javax.xml.stream.XMLOutputFactory;
import javax.xml.stream.XMLStreamException;
import org.codehaus.staxmate.SMOutputFactory;
import org.codehaus.staxmate.out.SMOutputDocument;
import org.codehaus.staxmate.out.SMOutputElement;
public class Test {
public static void main(String[] args) {
main("c:\\tmp\\empl.xml");
}
public static void main(String fname)
{
// 1: need output factory
SMOutputFactory outf = new SMOutputFactory(XMLOutputFactory.newInstance());
SMOutputDocument doc;
try {
doc = outf.createOutputDocument(new File(fname));
// (optional) 3: enable indentation (note spaces after backslash!)
doc.setIndentation("\n ", 1, 1);
// 4. comment regarding generation time
doc.addComment(" generated: "+new java.util.Date().toString());
SMOutputElement empl = doc.addElement("employee");
empl.addAttribute(/*namespace*/ null, "id", 123);
SMOutputElement name = empl.addElement("name");
name.addElement("first").addCharacters("Tatu");
name.addElement("last").addCharacters("Saloranta");
// 10. close the document to close elements, flush output
doc.closeRoot();
} catch (XMLStreamException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Now when I invoke the main(String) method from my code the problem still persists whereas if I just run class Test as it is it works smoothly! My code involves database initializations and some other product specific actions.
I am lost, any thoughts on how should I proceed with this?

Indentation works with Woodstox API
WstxOutputFactory factory = new WstxOutputFactory();
factory.setProperty(WstxOutputFactory.P_AUTOMATIC_EMPTY_ELEMENTS, true);
SMOutputFactory outf = new SMOutputFactory(factory);
doc = outf.createOutputDocument(fout);
doc.setIndentation("\n ", 1, 1);

Below works for me -
context.setIndentation("\r\n\t\t\t\t\t\t\t\t", 2, 1); // indent by windows lf and 1 tab per level