net.sf.kdgcommons.html

Class HtmlUtil

java.lang.Object

net.sf.kdgcommons.html.HtmlUtil

public class HtmlUtil
extends Object

Static methods for working with HTML content, typically in a string.

Constructor Summary

Constructors

Constructor and Description
HtmlUtil()

Method Summary

Modifier and Type	Method and Description
static void	appendAttribute(StringBuilder buf, String name, Object value) Appends an escaped attribute (name='value') to the passed buffer, which is assumed to contain an in-process HTML element string.
static void	appendOptionalAttribute(StringBuilder buf, String name, Object value) Appends an escaped attribute (name='value') to the passed buffer, which is assumed to contain an in-process HTML element string, iff the attribute value is neither null nor an empty string.
static String	buildQueryString(Map<?,?> params, boolean ignoreEmpty) Constructs a query string out of a parameter map, URL-encoding values.
static String	escape(String src) Replaces characters in the passed string with entities: < replaced with &lt; > replaced with &gt; & replaced with &amp; " replaced with &quot; ' replaced with &#39; (this allows single quotes to be used in attribute values that are delimited by single quotes) any non-ASCII character (ie, those with codepoints > 127) with a hexadecimal Unicode escape If passed null, returns an empty string.
static String	htmlToText(String input) Converts HTML to plain text, according to the following rules: Replaces any newlines or carriage returns in the source text with single spaces.
static Map<String,String>	parseQueryString(String query, boolean ignoreEmpty) Parses a query string into a parameter map, decoding values as needed.
static String	unescape(String src) Replaces entity references in the passed string with their character values.
static String	urlDecode(String src) A wrapper around URLDecoder that always decodes as UTF-8, and replaces its checked exception with a RuntimeException (that should never be thrown).
static String	urlEncode(String src) A wrapper around URLEncoder that always encodes to UTF-8, replaces its checked exception with a RuntimeException (that should never be thrown), and encodes spaces as "%20" rather than "+".

Methods inherited from class java.lang.Object

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

Constructor Detail

HtmlUtil

public HtmlUtil()

Method Detail

urlEncode

public static String urlEncode(String src)

A wrapper around URLEncoder that always encodes to UTF-8, replaces its checked exception with a RuntimeException (that should never be thrown), and encodes spaces as "%20" rather than "+".

If passed null, will return an empty string.

urlDecode

public static String urlDecode(String src)

A wrapper around URLDecoder that always decodes as UTF-8, and replaces its checked exception with a RuntimeException (that should never be thrown).

If passed null, will return an empty string.

escape

public static String escape(String src)

Replaces characters in the passed string with entities:

• < replaced with &lt;
• > replaced with &gt;
• & replaced with &amp;
• " replaced with &quot;
• ' replaced with &#39; (this allows single quotes to be used in attribute values that are delimited by single quotes)
• any non-ASCII character (ie, those with codepoints > 127) with a hexadecimal Unicode escape

If passed null, returns an empty string.

unescape

public static String unescape(String src)

Replaces entity references in the passed string with their character values. Supports the following four named entities, as well as both hexadecimal and decimal numeric entities.

• &lt;
• &gt;
• &amp;
• &quot;

If passed null, returns an empty string. If passed a string without any entity escapes, returns that string unchanged.

appendAttribute

public static void appendAttribute(StringBuilder buf,
                                   String name,
                                   Object value)

Appends an escaped attribute (name='value') to the passed buffer, which is assumed to contain an in-process HTML element string.

If value is null, will append the attribute with an empty string value. See appendOptionalAttribute(java.lang.StringBuilder, java.lang.String, java.lang.Object) if you want to skip null values.

appendOptionalAttribute

public static void appendOptionalAttribute(StringBuilder buf,
                                           String name,
                                           Object value)

Appends an escaped attribute (name='value') to the passed buffer, which is assumed to contain an in-process HTML element string, iff the attribute value is neither null nor an empty string.

buildQueryString

public static String buildQueryString(Map<?,?> params,
                                      boolean ignoreEmpty)

Constructs a query string out of a parameter map, URL-encoding values. This is often simpler than URLBuilder, but does not support multiple values per parameter.

Parameters:

params - The map of parameter values. This must contain only scalar values: both key and value are converted to strings before being added to the query string.

ignoreEmpty - If true, entries with empty or null values are not added to the string; if false, they're added in the form "name="

Returns:

The query string, consisting of "name=value" pairs separated by ampersands. There's no leading question mark.

parseQueryString

public static Map<String,String> parseQueryString(String query,
                                                  boolean ignoreEmpty)

Parses a query string into a parameter map, decoding values as needed. Does not support multiple parameter values; later values will overwrite earlier.

Parameters:

query - The query string: zero or more name=value pairs separated by ampersands, with or without a leading question mark.

ignoreEmpty - If true, ignores any entries without a value (eg, "name="; if false these are added to the map with an empty string for the value.

Returns:

A map of the name-value pairs. Caller is permitted to modify this map.

Throws:

RuntimeException - on any failure.

htmlToText

public static String htmlToText(String input)

Converts HTML to plain text, according to the following rules:

• Replaces any newlines or carriage returns in the source text with single spaces.
• Replaces <P> and <BR> with newlines.
• Replaces <LI> with newline followed by "* ".
• Removes all other tags, including their attributes.
• Leaves text behind.

Since:

1.0.2