Package org.apache.velocity.tools.generic

Class DisplayTool

  • All Implemented Interfaces:
    java.io.Serializable
    @DefaultKey("display")
@ValidScope("application")
public class DisplayTool
extends LocaleConfig
implements java.io.Serializable
    Provides general utility methods for controlling the display of references. Currently, this class contains methods for "pretty printing" an array or Collection, methods for truncating the string value of a reference at a configured or specified length, methods for displaying an alternate value when a specified value is null, a method for generating whitespace, a "printf" type of method for formatting messages, and methods for forcing values into "cells" of equal size (via truncation or padding with whitespace).

    Example Use: 

     tools.xml...
 <tools>
   <toolbox scope="application">
     <tool class="org.apache.velocity.tools.generic.DisplayTool"/>
   </toolbox>
 </tools>

 template...
   #set( $list = [1..5] )
   $display.list($list)
   $display.truncate("This is a long string.", 10)
   Not Null: $display.alt("not null", "--")
   Null: $display.alt($null, "--")

 output...
   1, 2, 3, 4 and 5
   This is...
   Not Null: not null
   Null: --
    Since:
    VelocityTools 2.0
    Version:
    $Id: DisplayTool.java 463298 2006-10-12 16:10:32Z henning $
    Author:
    Sean Legassick, Daniel Rall, Nathan Bubna
    See Also:
    Serialized Form

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  DisplayTool.Measurements
      Measures the dimensions of the string given to its constructor.

    • Constructor Summary

      Constructors 
      Constructor Description
      DisplayTool()  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      java.lang.Object alt​(java.lang.Object checkMe)
      Returns a configured default value if specified value is null.
      java.lang.Object alt​(java.lang.Object checkMe, java.lang.Object alternate)
      Returns the second argument if first argument specified is null.
      java.lang.String br​(java.lang.Object obj)
      Inserts HTML line break tag (<br />) in front of all newline characters of the string value of the specified object and returns the resulting string.
      java.lang.String capitalize​(java.lang.Object capitalizeMe)
      Changes the first character of the string value of the specified object to upper case and returns the resulting string.
      java.lang.String cell​(java.lang.Object obj)
      Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the default cell size.
      java.lang.String cell​(java.lang.Object obj, int cellsize)
      Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the specified cell size.
      java.lang.String cell​(java.lang.Object obj, int cellsize, java.lang.String suffix)
      Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the specified cell size.
      java.lang.String cell​(java.lang.Object obj, java.lang.String suffix)
      Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the default cell size.
      protected void configure​(ValueParser values)
      Does the actual configuration.
      protected java.lang.String format​(java.util.Collection list, java.lang.String delim, java.lang.String finaldelim, java.lang.String property)
      Does the actual formatting of the collection.
      java.lang.String[] getAllowedTags()  
      int getCellLength()  
      java.lang.String getCellSuffix()  
      java.lang.String getDefaultAlternate()  
      java.lang.String getListDelimiter()  
      java.lang.String getListFinalDelimiter()  
      protected java.lang.Object getProperty​(java.lang.Object object, java.lang.String property)
      Safely retrieves the specified property from the specified object.
      boolean getTruncateAtWord()  
      int getTruncateLength()  
      java.lang.String getTruncateSuffix()  
      java.lang.String list​(java.lang.Object list)
      Formats a collection or array into the form "A, B and C".
      java.lang.String list​(java.lang.Object list, java.lang.String delim)
      Formats a collection or array into the form "A<delim>B<delim>C".
      java.lang.String list​(java.lang.Object list, java.lang.String delim, java.lang.String finaldelim)
      Formats a collection or array into the form "A<delim>B<finaldelim>C".
      java.lang.String list​(java.lang.Object list, java.lang.String delim, java.lang.String finaldelim, java.lang.String property)
      Formats a specified property of collection or array of objects into the form "A<delim>B<finaldelim>C".
      DisplayTool.Measurements measure​(java.lang.Object measureMe)
      Returns the DisplayTool.Measurements of the string value of the specified object.
      java.lang.String message​(java.lang.String format, java.lang.Object... args)
      Uses MessageFormat to format the specified String with the specified arguments.
      java.lang.String plural​(int value, java.lang.String singular)
      Builds plural form of a passed word if 'value' is plural, otherwise returns 'singular'.
      java.lang.String plural​(int value, java.lang.String singular, java.lang.String plural)
      Returns 'plural' parameter if passed 'value' is plural, otherwise 'singular' is returned.
      java.lang.String printf​(java.lang.String format, java.lang.Object... args)
      Uses String.format(Locale,String,Object...) to format the specified String with the specified arguments.
      protected void setAllowedTags​(java.lang.String[] tags)  
      protected void setCellLength​(int maxlen)  
      protected void setCellSuffix​(java.lang.String suffix)  
      protected void setDefaultAlternate​(java.lang.String dflt)  
      protected void setListDelimiter​(java.lang.String delim)  
      protected void setListFinalDelimiter​(java.lang.String finalDelim)  
      protected void setTruncateAtWord​(boolean atWord)  
      protected void setTruncateLength​(int maxlen)  
      protected void setTruncateSuffix​(java.lang.String suffix)  
      java.lang.String space​(int length)
      Returns a string of spaces of the specified length.
      java.lang.String stripTags​(java.lang.Object obj)
      Removes HTML tags from the string value of the specified object and returns the resulting string.
      java.lang.String stripTags​(java.lang.Object obj, java.lang.String... allowedTags)
      Removes all not allowed HTML tags from the string value of the specified object and returns the resulting string.
      java.lang.String truncate​(java.lang.Object truncateMe)
      Limits the string value of 'truncateMe' to the configured max length in characters (default is 30 characters).
      java.lang.String truncate​(java.lang.Object truncateMe, int maxLength)
      Limits the string value of 'truncateMe' to 'maxLength' characters.
      java.lang.String truncate​(java.lang.Object truncateMe, int maxLength, java.lang.String suffix)
      Limits the string value of 'truncateMe' to the specified max length in characters.
      java.lang.String truncate​(java.lang.Object truncateMe, int maxLength, java.lang.String suffix, boolean defaultTruncateAtWord)
      Limits the string value of 'truncateMe' to the latest complete word within the specified maxLength.
      java.lang.String truncate​(java.lang.Object truncateMe, java.lang.String suffix)
      Limits the string value of 'truncateMe' to the configured max length in characters (default is 30 characters).
      java.lang.String uncapitalize​(java.lang.Object uncapitalizeMe)
      Changes the first character of the string value of the specified object to lower case and returns the resulting string.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • DisplayTool

        public DisplayTool()

    • Method Detail

      • configure

        protected void configure​(ValueParser values)
        Does the actual configuration. This is protected, so subclasses may share the same ValueParser and call configure at any time, while preventing templates from doing so when configure(Map) is locked.
        Overrides:
        configure in class LocaleConfig
        Parameters:
        values - configuration values

      • getListDelimiter

        public java.lang.String getListDelimiter()

      • setListDelimiter

        protected void setListDelimiter​(java.lang.String delim)

      • getListFinalDelimiter

        public java.lang.String getListFinalDelimiter()

      • setListFinalDelimiter

        protected void setListFinalDelimiter​(java.lang.String finalDelim)

      • getTruncateLength

        public int getTruncateLength()

      • setTruncateLength

        protected void setTruncateLength​(int maxlen)

      • getTruncateSuffix

        public java.lang.String getTruncateSuffix()

      • setTruncateSuffix

        protected void setTruncateSuffix​(java.lang.String suffix)

      • getTruncateAtWord

        public boolean getTruncateAtWord()

      • setTruncateAtWord

        protected void setTruncateAtWord​(boolean atWord)

      • getCellSuffix

        public java.lang.String getCellSuffix()

      • setCellSuffix

        protected void setCellSuffix​(java.lang.String suffix)

      • getCellLength

        public int getCellLength()

      • setCellLength

        protected void setCellLength​(int maxlen)

      • getDefaultAlternate

        public java.lang.String getDefaultAlternate()

      • setDefaultAlternate

        protected void setDefaultAlternate​(java.lang.String dflt)

      • getAllowedTags

        public java.lang.String[] getAllowedTags()

      • setAllowedTags

        protected void setAllowedTags​(java.lang.String[] tags)

      • list

        public java.lang.String list​(java.lang.Object list)
        Formats a collection or array into the form "A, B and C".
        Parameters:
        list - A collection or array.
        Returns:
        A String.

      • list

        public java.lang.String list​(java.lang.Object list,
                             java.lang.String delim)
        Formats a collection or array into the form "A<delim>B<delim>C".
        Parameters:
        list - A collection or array.
        delim - A String.
        Returns:
        A String.

      • list

        public java.lang.String list​(java.lang.Object list,
                             java.lang.String delim,
                             java.lang.String finaldelim)
        Formats a collection or array into the form "A<delim>B<finaldelim>C".
        Parameters:
        list - A collection or array.
        delim - A String.
        finaldelim - A String.
        Returns:
        A String.

      • list

        public java.lang.String list​(java.lang.Object list,
                             java.lang.String delim,
                             java.lang.String finaldelim,
                             java.lang.String property)
        Formats a specified property of collection or array of objects into the form "A<delim>B<finaldelim>C".
        Parameters:
        list - A collection or array.
        delim - A String.
        finaldelim - A String.
        property - An object property to format.
        Returns:
        A String.

      • format

        protected java.lang.String format​(java.util.Collection list,
                                  java.lang.String delim,
                                  java.lang.String finaldelim,
                                  java.lang.String property)
        Does the actual formatting of the collection.
        Parameters:
        list - collection of objects to format
        delim - delimiter
        finaldelim - final delimiter
        property - objects property to use
        Returns:
        formatted string

      • message

        public java.lang.String message​(java.lang.String format,
                                java.lang.Object... args)
        Uses MessageFormat to format the specified String with the specified arguments. If there are no arguments, then the String is returned directly. Please note that the format required here is quite different from that of printf(String,Object...).
        Parameters:
        format - format string
        args - arguments
        Returns:
        formatted message
        Since:
        VelocityTools 2.0

      • printf

        public java.lang.String printf​(java.lang.String format,
                               java.lang.Object... args)
        Uses String.format(Locale,String,Object...) to format the specified String with the specified arguments. Please note that the format required here is quite different from that of message(String,Object...).
        Parameters:
        format - format string
        args - printf arguments
        Returns:
        formatted string
        Since:
        VelocityTools 2.0
        See Also:
        Formatter

      • truncate

        public java.lang.String truncate​(java.lang.Object truncateMe)
        Limits the string value of 'truncateMe' to the configured max length in characters (default is 30 characters). If the string gets curtailed, the configured suffix (default is "...") is used as the ending of the truncated string.
        Parameters:
        truncateMe - The value to be truncated.
        Returns:
        A String.

      • truncate

        public java.lang.String truncate​(java.lang.Object truncateMe,
                                 int maxLength)
        Limits the string value of 'truncateMe' to 'maxLength' characters. If the string gets curtailed, the configured suffix (default is "...") is used as the ending of the truncated string.
        Parameters:
        maxLength - An int with the maximum length.
        truncateMe - The value to be truncated.
        Returns:
        A String.

      • truncate

        public java.lang.String truncate​(java.lang.Object truncateMe,
                                 java.lang.String suffix)
        Limits the string value of 'truncateMe' to the configured max length in characters (default is 30 characters). If the string gets curtailed, the specified suffix is used as the ending of the truncated string.
        Parameters:
        truncateMe - The value to be truncated.
        suffix - A String.
        Returns:
        A String.

      • truncate

        public java.lang.String truncate​(java.lang.Object truncateMe,
                                 int maxLength,
                                 java.lang.String suffix)
        Limits the string value of 'truncateMe' to the specified max length in characters. If the string gets curtailed, the specified suffix is used as the ending of the truncated string.
        Parameters:
        truncateMe - The value to be truncated.
        maxLength - An int with the maximum length.
        suffix - A String.
        Returns:
        A String.

      • truncate

        public java.lang.String truncate​(java.lang.Object truncateMe,
                                 int maxLength,
                                 java.lang.String suffix,
                                 boolean defaultTruncateAtWord)
        Limits the string value of 'truncateMe' to the latest complete word within the specified maxLength. If the string gets curtailed, the specified suffix is used as the ending of the truncated string.
        Parameters:
        truncateMe - The value to be truncated.
        maxLength - An int with the maximum length.
        suffix - A String.
        defaultTruncateAtWord - Truncate at a word boundary if true.
        Returns:
        A String.

      • space

        public java.lang.String space​(int length)
        Returns a string of spaces of the specified length.
        Parameters:
        length - the number of spaces to return
        Returns:
        string of spaces

      • cell

        public java.lang.String cell​(java.lang.Object obj)
        Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the default cell size.
        Parameters:
        obj - the value to be put in the 'cell'
        Returns:
        truncated/padded string

      • cell

        public java.lang.String cell​(java.lang.Object obj,
                             int cellsize)
        Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the specified cell size.
        Parameters:
        obj - the value to be put in the 'cell'
        cellsize - the size of the cell into which the object must be placed
        Returns:
        truncated/padded string

      • cell

        public java.lang.String cell​(java.lang.Object obj,
                             java.lang.String suffix)
        Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the default cell size. If truncation is necessary, the specified suffix will replace the end of the string value to indicate that.
        Parameters:
        obj - the value to be put in the 'cell'
        suffix - the suffix to put at the end of any values that need truncating to indicate that they've been truncated
        Returns:
        truncated/padded string

      • cell

        public java.lang.String cell​(java.lang.Object obj,
                             int cellsize,
                             java.lang.String suffix)
        Truncates or pads the string value of the specified object as necessary to ensure that the returned string's length equals the specified cell size.
        Parameters:
        obj - the value to be put in the 'cell'
        cellsize - the size of the cell into which the object must be placed
        suffix - the suffix to put at the end of any values that need truncating to indicate that they've been truncated
        Returns:
        truncated/padded string

      • capitalize

        public java.lang.String capitalize​(java.lang.Object capitalizeMe)
        Changes the first character of the string value of the specified object to upper case and returns the resulting string.
        Parameters:
        capitalizeMe - The value to be capitalized.
        Returns:
        capitalized string

      • uncapitalize

        public java.lang.String uncapitalize​(java.lang.Object uncapitalizeMe)
        Changes the first character of the string value of the specified object to lower case and returns the resulting string.
        Parameters:
        uncapitalizeMe - The value to be uncapitalized.
        Returns:
        uncapitalized string

      • alt

        public java.lang.Object alt​(java.lang.Object checkMe)
        Returns a configured default value if specified value is null.
        Parameters:
        checkMe - object to check
        Returns:
        a configured default value if the specified value is null.

      • alt

        public java.lang.Object alt​(java.lang.Object checkMe,
                            java.lang.Object alternate)
        Returns the second argument if first argument specified is null.
        Parameters:
        checkMe - object to check
        alternate - alternate value
        Returns:
        the second argument if the first is null.

      • br

        public java.lang.String br​(java.lang.Object obj)
        Inserts HTML line break tag (<br />) in front of all newline characters of the string value of the specified object and returns the resulting string.
        Parameters:
        obj - source object
        Returns:
        string with added br tags

      • stripTags

        public java.lang.String stripTags​(java.lang.Object obj)
        Removes HTML tags from the string value of the specified object and returns the resulting string.
        Parameters:
        obj - source object
        Returns:
        text stripped from HTML tags

      • stripTags

        public java.lang.String stripTags​(java.lang.Object obj,
                                  java.lang.String... allowedTags)
        Removes all not allowed HTML tags from the string value of the specified object and returns the resulting string.
        Parameters:
        obj - source object
        allowedTags - An array of allowed tag names (i.e. "h1","br","img")
        Returns:
        text stripped from given HTML tags

      • plural

        public java.lang.String plural​(int value,
                               java.lang.String singular)
        Builds plural form of a passed word if 'value' is plural, otherwise returns 'singular'. Plural form is built using some basic English language rules for nouns which does not guarantee correct syntax of a result in all cases.
        Parameters:
        value - count
        singular - Singular form of a word.
        Returns:
        guessed plural

      • plural

        public java.lang.String plural​(int value,
                               java.lang.String singular,
                               java.lang.String plural)
        Returns 'plural' parameter if passed 'value' is plural, otherwise 'singular' is returned.
        Parameters:
        value - count
        singular - Singular form of a word.
        plural - Plural form of a word.
        Returns:
        guessed plural

      • getProperty

        protected java.lang.Object getProperty​(java.lang.Object object,
                                       java.lang.String property)
        Safely retrieves the specified property from the specified object. Subclasses that wish to perform more advanced, efficient, or just different property retrieval methods should override this method to do so.
        Parameters:
        object - target object
        property - target property
        Returns:
        property value
        Throws:
        java.lang.IllegalArgumentException - if it wasn't possible to get the object's property value