Package de.stefanfrings.utils

Class TextTemplate

java.lang.Object
de.stefanfrings.utils.TextTemplate
public class TextTemplate extends Object
Text document creation with templates.

Different to Freemarker/Velocity, this class generates text documents from templates without the need of a model. The application actively writes into the document to fill variables.

This class has been designed for cases where a very simple more restricted template syntax is required.

Example template file: 

 Hello {username}, how are you?

 {if locked}
     Your account is locked.
 {else locked}
     Welcome on our system.
 {end locked}

 The following users are on-line:
     Username       Time
 {loop user}
     {user.name}     {user.time}
 {end user}

Example code to fill this template: 

 File file=new File("/temp/test.tpl");
 TextTemplate t=new TextTemplate(file,"UTF-8");
 t.variable("user", "Stefan");
 t.condition("locked",false);
 t.loop("user",2);
 t.variable("user0.name,"Markus");
 t.variable("user0.time,"8:30");
 t.variable("user1.name,"Roland");
 t.variable("user1.time,"8:45");

The code example above shows how variable within loops are numbered. Counting starts with 0. Loops can be nested, for example: 

 <table>
 {loop row}
     <tr>
     {loop row.column}
         <td>{row.column.value}</td>
     {end row.column}
     </tr>
 {end row}
 </table>

Example code to fill this nested loop: 

 t.loop("row",10);
 for (int i=0; i<10; i++) {
     t.loop("row"+i+".column",10);
     for (int j=0; j<10; j++) {
         t.variable("row"+i+".column+"j"+".value","Hello");
     }
 }
This creates a HTML table with 10 rows and each with 10 columns. The fields are filled with the string "Hello".
Author:
Stefan Frings, http://stefanfrings.de/javautils

  • Constructor Details

    • TextTemplate

      public TextTemplate(CharSequence template, String sourceName)
      Constructor that copies a template from CharSequence.
      Parameters:
      template - The template as CharSequence
      sourceName - Symbolic name of the template, used in error messages loops cause an exception. If false, only syntax errors cause an exception.

    • TextTemplate

      public TextTemplate(CombinedURL url, int connTimeout, int readTimeout, String encoding) throws IOException
      Constructor that reads a template from an URL.
      Parameters:
      url - The URL of the template file
      connTimeout - Timeout connectng to the server
      readTimeout - Timeout reading the from the server
      encoding - Default encoding, used if the server does not provide this information
      Throws:
      IOException - In case of an I/O error.

    • TextTemplate

      public TextTemplate(URL url, String encoding) throws IOException
      Constructor that reads a template from a local URL. To read from a remote URL, use TextTemplate(CombinedURL url, int connTimeout, int readTimeout, String encoding) instead.
      Parameters:
      url - The URL of the template file
      encoding - Default encoding, used if the server does not provide this information
      Throws:
      IOException - In case of an I/O error.

    • TextTemplate

      public TextTemplate(InputStream stream, String sourceName, String encoding) throws IOException
      Constructor that reads a template from an InputStream. To read from a remote URL, use TextTemplate(CombinedURL url, int connTimeout, int readTimeout, String encoding) instead.
      Parameters:
      stream - The source stream
      sourceName - Symbolic name of the template, used in error messages
      encoding - Default encoding, used if the server does not provide this information
      Throws:
      IOException - In case of an I/O error.

    • TextTemplate

      public TextTemplate(File file, String encoding) throws IOException
      Constructor that reads a template from a file.
      Parameters:
      file - The template file.
      encoding - Encoding of the file, null is allowed to use the default.
      Throws:
      IOException - In case of an I/O error.

  • Method Details

    • toString

      public String toString()
      Return the filled template as String.
      Overrides:
      toString in class Object
      Returns:
      new Document

    • check

      public boolean check()
      Check if the template contains unused tags. If there are such tags, then the function logs a warning.
      Returns:
      true if there are one or more unused tags

    • variable

      public int variable(String name, String value) throws TemplateException
      Replace a variable by a value. This affects tags with the syntax {name}.
      Parameters:
      name - Name of the variable
      value - New value, null produces in an empty string.
      Returns:
      The number of variables that have been replaced
      Throws:
      TemplateException - If the template contains a syntx error

    • condition

      public int condition(String name, boolean value) throws TemplateException
      Set a condition. This affects tags with the syntax
      • {if name}...{end name}
      • {if name}...{else name}...{end name}
      • {ifnot name}...{end name}
      • {ifnot name}...{else name}...{end name}
      Parameters:
      name - Name of the condition
      value - Value of the condition
      Returns:
      The number of conditions that have been processed
      Throws:
      TemplateException - If the template contains a syntx error

    • loop

      public int loop(String name, int repetitions) throws TemplateException
      Set repetitions of a loop. This affects tags with the syntax
      • {loop name}...{end name}
      • {loop name}...{else name}...{end name}
      Parameters:
      name - Name of the loop
      repetitions - The number of repetitions
      Returns:
      The number of conditions that have been processed
      Throws:
      TemplateException - If the template contains a syntx error