Added <hs:cause/> and <hs:code/> tags and associated parameters.

ethauvin · Dec 4, 2015 · da35797 · da35797
1 parent 92a6bb2
commit da35797
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Showing 9 changed files with 485 additions and 40 deletions.
diff --git a/README.md b/README.md
@@ -10,9 +10,10 @@ For example:
 <%@ page isErrorPage="true" %>
 <%@ taglib prefix="hs" uri="http://erik.thauvin.net/taglibs/httpstatus" %>
 <html><head>
-<title>${pageContext.errorData.statusCode} <hs:reason default="Server Error"/></title>
+<title><hs:code/> <hs:reason default="Server Error"/></title>
 </head>
 <h1><hs:reason default="Server Error"/></h1>
+Cause: <pre><hs:cause default="Unable to complete your request."/></pre>
 ...
 ```
 
@@ -29,12 +30,37 @@ would display on a [501 status code](http://www.w3.org/Protocols/rfc2616/rfc2616
 
 ----
 
-The **<hs:reason>** tag attributes are:
+## hs:cause
 
-Attribute    | Description                                                                   | Required
------------- | ----------------------------------------------------------------------------- | --------
-`statusCode` | The HTTP status error code. If not specified the current status code is used. | No
-`default`    | The fallback value to output.                                                 | No
+The `<hs:cause/>` tag displays the cause of current HTTP status code, if any. A shorthand for:
+
+```jsp
+<%= pageContext.getErrorData().getThrowable().getCause().getLocalizedMessage() %>
+```
+
+Optional attributes are:
+
+Attribute   | Description
+----------- | -------------------------------------------------------------------------------------------
+`default`   | The fallback value to output, if no cause is available.
+`escapeXml` | Converts &lt;,&gt;,&amp;,'," to their corresponding [entity codes](http://dev.w3.org/html5/html-author/charref). Value is true by default.
+
+## hs:code
+The `<hs:code/>` tag displays the current HTTP status code, if any. A shorthand for:
+
+```jsp
+<%= pageContext.getErrorData().getStatusCode() %>
+```
+
+## hs:reason
+
+The `<hs:reason/>` tag displays the reason for a HTTP status code, if any. Optional attributes are:
+
+Attribute   | Description
+----------- | -------------------------------------------------------------------------------------------
+`code`      | The HTTP status error code. If not specified the current status code is used.
+`default`   | The fallback value to output, if no reason is available.
+`escapeXml` | Converts &lt;,&gt;,&amp;,'," to their corresponding [entity codes](http://dev.w3.org/html5/html-author/charref). Value is true by default.
 
 The reasons are defined in a [ResourceBundle](http://docs.oracle.com/javase/8/docs/api/java/util/ResourceBundle.html) properties as follows:
 

diff --git a/src/main/java/net/thauvin/erik/httpstatus/Utils.java b/src/main/java/net/thauvin/erik/httpstatus/Utils.java
@@ -0,0 +1,134 @@
+/*
+ * Utils.java
+ *
+ * Copyright (c) 2015, Erik C. Thauvin (erik@thauvin.net)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of the author nor the names of its contributors may be
+ * used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.thauvin.erik.httpstatus;
+
+import java.io.IOException;
+import java.io.Writer;
+
+/**
+ * The <code>Utils</code> class.
+ *
+ * @author <a href="mailto:erik@thauvin.net">Erik C. Thauvin</a>
+ * @created 2015-12-03
+ * @since 1.0
+ */
+public class Utils
+{
+
+	/**
+	 * Disables the default constructor.
+	 *
+	 * @throws UnsupportedOperationException if an error occurred. if the constructor is called.
+	 */
+	private Utils()
+			throws UnsupportedOperationException
+	{
+		throw new UnsupportedOperationException("Illegal constructor call.");
+	}
+
+	/**
+	 * Writes a string value.
+	 *
+	 * @param out The writer to output the value to.
+	 * @param value The string value.
+	 * @param defaultValue The default value.
+	 * @param xml The xml flag.
+	 */
+	public static void outWrite(Writer out, String value, String defaultValue, boolean xml)
+			throws IOException
+	{
+		if (xml)
+		{
+			if (value != null)
+			{
+				out.write(escapeXml(value));
+			}
+			else if (defaultValue != null)
+			{
+				out.write(escapeXml(defaultValue));
+			}
+		}
+		else
+		{
+			if (value != null)
+			{
+				out.write(value);
+			}
+			else if (defaultValue != null)
+			{
+				out.write(defaultValue);
+			}
+		}
+	}
+
+	/**
+	 * Escapes a string value.
+	 *
+	 * @param value The string value to escape.
+	 *
+	 * @return The escaped string value.
+	 */
+	public static String escapeXml(String value)
+	{
+		final StringBuilder escaped = new StringBuilder();
+
+		for (int i = 0; i < value.length(); i++)
+		{
+			final char c = value.charAt(i);
+			switch (c)
+			{
+				case '<':
+					escaped.append("&lt;");
+					break;
+				case '>':
+					escaped.append("&gt;");
+					break;
+				case '&':
+					escaped.append("&amp;");
+					break;
+				case '\'':
+					escaped.append("&#039;");
+					break;
+				case '"':
+					escaped.append("&#034;");
+					break;
+				default:
+					escaped.append(c);
+					break;
+			}
+		}
+
+		return escaped.toString();
+	}
+}
diff --git a/src/main/java/net/thauvin/erik/httpstatus/taglibs/CauseTag.java b/src/main/java/net/thauvin/erik/httpstatus/taglibs/CauseTag.java
@@ -0,0 +1,72 @@
+/*
+ * CauseTag.java
+ *
+ * Copyright (c) 2015, Erik C. Thauvin (erik@thauvin.net)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of the author nor the names of its contributors may be
+ * used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.thauvin.erik.httpstatus.taglibs;
+
+import net.thauvin.erik.httpstatus.Utils;
+
+import javax.servlet.jsp.JspException;
+import javax.servlet.jsp.JspWriter;
+import javax.servlet.jsp.PageContext;
+import java.io.IOException;
+
+/**
+ * The <code>CauseTag</code> class.
+ *
+ * @author <a href="mailto:erik@thauvin.net">Erik C. Thauvin</a>
+ * @created 2015-12-03
+ * @since 1.0
+ */
+public class CauseTag extends XmlSupport
+{
+	@Override
+	public void doTag()
+			throws JspException, IOException
+	{
+		final PageContext pageContext = (PageContext) getJspContext();
+		final JspWriter out = pageContext.getOut();
+
+		String cause;
+
+		try
+		{
+			cause = pageContext.getErrorData().getThrowable().getCause().getLocalizedMessage();
+		}
+		catch (NullPointerException ignore)
+		{
+			cause = defaultValue;
+		}
+
+		Utils.outWrite(out, cause, defaultValue, escapeXml);
+	}
+}
diff --git a/src/main/java/net/thauvin/erik/httpstatus/taglibs/CodeTag.java b/src/main/java/net/thauvin/erik/httpstatus/taglibs/CodeTag.java
@@ -0,0 +1,60 @@
+/*
+ * CodeTag.java
+ *
+ * Copyright (c) 2015, Erik C. Thauvin (erik@thauvin.net)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of the author nor the names of its contributors may be
+ * used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package net.thauvin.erik.httpstatus.taglibs;
+
+import javax.servlet.jsp.JspException;
+import javax.servlet.jsp.JspWriter;
+import javax.servlet.jsp.PageContext;
+import javax.servlet.jsp.tagext.SimpleTagSupport;
+import java.io.IOException;
+
+/**
+ * The <code>CodeTag</code> class.
+ *
+ * @author <a href="mailto:erik@thauvin.net">Erik C. Thauvin</a>
+ * @created 2015-12-03
+ * @since 1.0
+ */
+public class CodeTag extends SimpleTagSupport
+{
+	@Override
+	public void doTag()
+			throws JspException, IOException
+	{
+		final PageContext pageContext = (PageContext) getJspContext();
+		final JspWriter out = pageContext.getOut();
+
+		out.write(String.valueOf(pageContext.getErrorData().getStatusCode()));
+	}
+}