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ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 346 #LSDateFormat(Now(), "mm/dd/yyyy")#<br> #LSDateFormat(Now(), "d-mmm-yyyy")#<br> #LSDateFormat(Now(), "ddd, mmmm dd, yyyy")#<br> #LSDateFormat(Now(), "d/m/yy")#<br> #LSDateFormat(Now())#<br> <hr noshade> </cfoutput> </cfloop> </body> </html> Additional globalization tags and functions In addition to the tags and functions that are specifically for globalized applications, you might find the following useful when writing a globalized application: • All string manipulation functions. For more information, see the String functions list in “ColdFusion Functions” on page 636 in the CFML Reference. • The GetTimeZoneInfo function, which returns the time zone of the operating system. Handling data in ColdFusion Many of the issues involved with globalizing applications deal with processing data from the various sources supported by ColdFusion, including the following: • General character encoding issues • Locale-specific content • Input data from URLs and HTML forms • File data • Databases • E-mail • HTTP • LDAP • WDDX • COM • CORBA • Searching and indexing General character encoding issues Applications developed for earlier versions of ColdFusion that assumed that the character length of a string was the same as the byte length might produce errors in ColdFusion. The byte length of a string depends on the character encoding. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 347 Locale-specific content The following sections provide information on how to handle locale-specific content in pages that support multiple locales, and how to handle euro values. Generating multilocale content In an application that supports users in multiple locales and produces output that is specific to multiple locales, you call the SetLocale function in every request to set the locale for that specific request. When processing has completed, the locale should be set back to its previous value. One useful technique is to save the user’s desired locale in a Session variable once the user has selected it, and use the Session variable value to set the locale for each user request during the session. Supporting the euro The euro is the currency of many European countries, and ColdFusion supports the reading and writing of correctly formatted euro values. Unlike other supported currencies, the euro is not tied to any single country (or locale). The LSCurrencyFormat and LSParseCurrency functions rely on the underlying JVM for their operations, and the rules used for currencies depend on the JVM. For Sun JVMs, the 1.3 releases did not support euros and used the older country-specific currencies. The 1.4 releases use euros for all currencies that are in the euro zone as of 2002. If you are using a JVM that does not support the euro, use the LSEuroCurrencyFormat and LSParseEuroCurrency functions to format and parse euro values in locales that use euros as their currency. Input data from URLs and HTML forms A web application server receives character data from request URL parameters or as form data. The HTTP 1.1 standard only allows US-ASCII characters (0-127) for the URL specification and for message headers. This requires a browser to encode the non-ASCII characters in the URL, both address and parameters, by escaping (URL encoding) the characters using the “%xx” hexadecimal format. URL encoding, however, does not determine how the URL is used in a web document. It only specifies how to encode the URL. Form data uses the message headers to specify the encoding used by the request (Content headers) and the encoding used in the response (Accept headers). Content negotiation between the client and server uses this information. There are several techniques for handling both URL and form data entered in different character encodings. Handling URL strings URL requests to a server often contain name-value pairs as part of the request. For example, the following URL contains name-value pairs as part of the URL: http://company.com/prod_page.cfm?name=Stephen;ID=7645 As discussed previously, URL characters entered using any character encoding other than US-ASCII are URL- encoded in a hexadecimal format. However, by default, a web server assumes that the characters of a URL string are single-byte characters. One common method used to support non-ASCII characters within a URL is to include a name-value pair within the URL that defines the character encoding of the URL. For example, the following URL uses a parameter called encoding to define the character encoding of the URL parameters: http://company.com/prod_page.cfm?name=Stephen;ID=7645;encoding=Latin-1 Within the prod_page.cfm page, you can check the value of the encoding parameter before processing any of the other name-value pairs. This guarantees that you will handle the parameters correctly. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 348 You can also use the SetEncoding function to specify the character encoding of URL parameters. The SetEncoding function takes two parameters: the first specifies a variable scope and the second specifies the character encoding used by the scope. Since ColdFusion writes URL parameters to the URL scope, you specify "URL" as the scope parameter to the function. For example, if the URL parameters were passed using Shift-JIS, you could access them as follows: <cfscript> setEncoding("URL", "Shift_JIS"); writeoutput(URL.name); writeoutput(URL.ID); </cfscript> Note: To specify the Shift-JIS character encoding, use the Shift_JIS attribute, with an underscore (_), not a hyphen (-). Handling form data The HTML form tag and the ColdFusion cfform tag let users enter text on a page, then submit that text to the server. The form tags are designed to work only with single-byte character data. Since ColdFusion uses two bytes per character when it stores strings, ColdFusion converts each byte of the form input into a two-byte representation. However, if a user enters double-byte text into the form, the form interprets each byte as a single character, rather than recognize that each character is two bytes. This corrupts the input text, as the following example shows: 1 A customer enters three double-byte characters in a form, represented by six bytes. 2 The form returns the six bytes to ColdFusion as six characters. ColdFusion converts them to a representation using two bytes per input byte for a total of twelve bytes. 3 Outputting these characters results in corrupt information displayed to the user. To work around this issue, use the SetEncoding function to specify the character encoding of input form text. The SetEncoding function takes two parameters: the first specifies the variable scope and the second specifies the character encoding used by the scope. Since ColdFusion writes form parameters to the Form scope, you specify "Form" as the scope parameter to the function. If the input text is double-byte, ColdFusion preserves the two-byte representation of the text. The following example specifies that the form data contains Korean characters: <cfscript> setEncoding("FORM", "EUC-KR"); </cfscript> <h1> Form Test Result </h1> <strong>Form Values :</strong> <cfset text = "String = #form.input1# , Length = #len(Trim(form.input1))#"> <cfoutput>#text#</cfoutput> File data You use the cffile tag to write to and read from text files. By default, the cffile tag assumes that the text that you are reading, writing, copying, moving, or appending is in the JVM default file character encoding, which is typically the system default character encoding. For cffile action="Read", ColdFusion also checks for a byte order mark (BOM) at the start of the file; if there is one, it uses the character encoding that the BOM specifies. Problems can arise if the file character encoding does not correspond to JVM character encoding, particularly if the number of bytes used for characters in one encoding does not match the number of bytes used for characters in the other encoding. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 349 For example, assume that the JVM default file character encoding is ISO 8859-1, which uses a single byte for each character, and the file uses Shift-JIS, which uses a two-byte representation for many characters. When reading the file, the cffile tag treats each byte as an ISO 8859-1 character, and converts it into its corresponding two-byte Unicode representation. Because the characters are in Shift-JIS, the conversion corrupts the data, converting each two-byte Shift-JIS character into two Unicode characters. To enable the cffile tag to correctly read and write text that is not encoded in the JVM default character encoding, you can pass the charset attribute to it. Specify as a value the character encoding of the data to read or write, as the following example shows: <cffile action="read" charset="EUC-KR" file = "c:\web\message.txt" variable = "Message" > Databases ColdFusion applications access databases using drivers for each of the supported database types. The conversion of client native language data types to SQL data types is transparent and is done by the driver managers, database client, or server. For example, the character data (SQL CHAR, VARCHAR) you use with JDBC API is represented using Unicode-encoded strings. Database administrators configure data sources and usually are required to specify the character encodings for character column data. Many of the major vendors, such as Oracle, Sybase, and Informix, support storing character data in many character encodings, including Unicode UTF-8 and UTF-16. The database drivers supplied with ColdFusion correctly handle data conversions from the database native format to the ColdFusion Unicode format. You should not have to perform any additional processing to access databases. However, you should always check with your database administrator to determine how your database supports different character encodings. E-mail ColdFusion sends e-mail messages using the cfmail, cfmailparam, and cfmailpart tags. By default, ColdFusion sends mail in UTF-8 encoding. You can specify a different default encoding on the Mail page in the ColdFusion Administrator, and you can use the charset attribute of the cfmail and cfmailpart tags to specify the character encoding for a specific mail message or part of a multipart mail message. HTTP ColdFusion supports HTTP communication using the cfhttp and cfhttpparam tags and the GetHttpRequestData function. The cfhttp tag supports making HTTP requests. The cfhttp tag uses the Unicode UTF-8 encoding for passing data by default, and you can use the charset attribute to specify the character encoding. You can also use the cfhttpparam tag mimeType attribute to specify the MIME type and character set of a file. LDAP ColdFusion supports LDAP (Lightweight Directory Access Protocol) through the cfldap tag. LDAP uses the UTF- 8 encoding format, so you can mix all retrieved data with other data and safely manipulated it. No extra processing is required to support LDAP. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 350 WDDX ColdFusion supports the cfwddx tag. ColdFusion stores WDDX (Web Distributed Data Exchange) data as UTF-8 encoding, so it automatically supports double-byte character encodings. You do not have to perform any special processing to handle double-byte characters with WDDX. COM ColdFusion supports COM through the cfobject type="com" tag. All string data used in COM interfaces is constructed using wide characters (wchars), which support double-byte characters. You do not have to perform any special processing to interface with COM objects. CORBA ColdFusion supports CORBA through the cfobject type="corba" tag. The CORBA 2.0 interface definition language (IDL) basic type “String” used the Latin-1 character encoding, which used the full 8-bits (256) to represent characters. As long as you are using CORBA later than version 2.0, which includes support for the IDL types wchar and wstring, which map to Java types char and string respectively, you do not have to do anything to support double-byte characters. However, if you are using a version of CORBA that does not support wchar and wstring, the server uses char and string data types, which assume a single-byte representation of text. Searching and indexing ColdFusion supports Verity search through the cfindex, cfcollection, and cfsearch tags. To support multlingual searching, the ColdFusion product CD-ROM includes the Verity language packs that you install to support different languages. 351 Chapter 20: Debugging and Troubleshooting Applications ColdFusion provides detailed debugging information to help you resolve problems with your application. You configure ColdFusion to provide debugging information, and use the cftrace and cftimer tags to provide detailed information on code execution. You can also use tools for validating your code before you run it and troubleshoot particular problems. Note: Adobe Dreamweaver provides integrated tools for displaying and using ColdFusion debugging output. For infor- mation on using these tools, see the Dreamweaver online Help. Contents Configuring debugging in the ColdFusion Administrator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351 Using debugging information from browser pages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353 Controlling debugging information in CFML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361 Using the cftrace tag to trace execution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362 Using the cftimer tag to time blocks of code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366 Using the Code Compatibility Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367 Troubleshooting common problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368 Configuring debugging in the ColdFusion Administrator ColdFusion can provide important debugging information for every application page requested by a browser. The ColdFusion Administrator lets you specify which debugging information to make available and how to display it. The following sections briefly describe the Administrator settings. For more information, see the online Help for the Debugging pages. Debugging Settings page In the Administrator, the following options on the Debugging Settings page determine the information that ColdFusion displays in debugging output: ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 352 The following image shows a sample debugging output using the classic output format: Option Description Enable Robust Exception Information Enables the display of the following information when ColdFusion displays the exception error page. (Cleared by default.) • Path and URL of the page that caused the error • Line number and short snippet of the code where the error was identified • Any SQL statement and data source • Java stack trace Enable Debugging Enables debugging output. When this option is cleared, no debugging information is displayed, including all output of cftrace and cftimer calls. (Cleared by default.) You should disable debugging output on production servers. Doing so increases security by ensuring that users cannot see debugging information. It also improves server response times. You can also limit debugging output to specific IP addresses; for more information, see “Debugging IP addresses page” on page 353. Select Debugging Output Format Determines how to display debugging output: • The classic.cfm template (the default) displays information as plain HTML text at the bottom of the page. • The dockable.cfm template uses DHTML to display the debugging information using an expanding tree format in a separate window. This window can be either a floating pane or docked to the browser window. For more information on the dockable output format, see “Using the dockable.cfm output format” on page 360. Report Execution Times Lists ColdFusion pages that run as the result of an HTTP request and displays execution times, Cold- Fusion also highlights in red pages with processing times greater than the specified value, and you can select between a summary display or a more detailed, tree structured, display. General Debug Information Displays general information about the request: ColdFusion Version, Template, Time Stamp, User Locale, User Agent, User IP, and Host Name. Database Activity Displays debugging information about access to SQL data sources and stored procedures. (Selected by default.) Exception information Lists all ColdFusion exceptions raised in processing the request. (Selected by default.) Tracing information Displays an entry for each cftrace tag. When this option is cleared, the debugging output does not include tracing information, but the output page does include information for cftrace tags that specify inline="Yes". (Selected by default.) For more information on using the cftrace tag, see“Using the cftrace tag to trace execution” on page 362. Variables Enables the display of ColdFusion variable values. When this option is cleared, disables display of all ColdFusion variables in the debugging output. (Selected by default.) When enabled, ColdFusion displays the values of variables in the selected scopes. You can select to display the contents of any of the ColdFusion scopes except Variables, Attributes, Caller, and ThisTag. To enhance security, Application, Server, and Request variable display is disabled by default, Enable Performance Monitoring Allows the standard NT Performance Monitor application to display information about a running ColdFusion application server. Enable CFSTAT Enables you to use of the cfstat command line utility to monitor real-time performance. This utility displays the same information that ColdFusion writes to the NT System Monitor, without using the System Monitor application. For information on the cfstat utility, see Configuring and Administering ColdFusion. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 353 Debugging IP addresses page By default, when you enable debugging output, the output is visible only to local users (that is, via IP address 127.0.0.1). You can specify additional IP addresses whose users can see debugging output, or even disable output to local users. In the Administrator, use the Debugging IPs page to specify the addresses that can receive debugging messages. Note: If you must enable debugging on a production server, for example to help locate the cause of a difficult problem, use the Debugging IP Addresses page to limit the output to your development systems and prevent clients from seeing the debugging information. Using debugging information from browser pages The ColdFusion debugging output that you configure in the Administrator displays whenever an HTML request completes. It represents the server conditions at the end of the request. For information on displaying debugging information while a request is processed, see “Using the cftrace tag to trace execution” on page 362. The following image shows a sample collapsed debugging output using the dockable.cfm debugging output format. The next sections show each of the debugging sections and describe how you can use the information they display. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 354 General debugging information ColdFusion displays general debugging information. In the classic.cfm output format, the information is at the top of the debugging output. In the dockable.cfm output format, it looks like the following image: (In the classic.cfm output format, the section is first in the debugging output and has no heading.) The general debugging information includes the following values. The table lists the names used in the classic output template view. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 355 Execution Time The Execution Time section displays the time required to process the request. It displays information about the time required to process all pages required for the request, including the Application.cfc, Application.cfm, and OnRequestEnd.cfm pages, if used, and any CFML custom tags, pages included by the cfinclude tag, and any ColdFusion component (CFC) pages. To display execution time for a specific block of code, use the cftimer tag. You can display the execution time in two formats: • Summary • Tree Note: Execution tine decreases substantially between the first and second time you use a page after creating it or changing it. The first time ColdFusion uses a page it compiles the page into Java bytecode, which the server saves and loads into memory. Subsequent uses of unmodified pages do not require recompilation of the code, and therefore are substantially faster. Summary execution time format The summary format displays one entry for each ColdFusion page processed during the request. If a page is processed multiple times it appears only once in the summary. For example, if a custom tag gets called three time in a request, it appears only once in the output. In the classic.cfm output format, the summary format looks like the following image: The following table describes the display fields: Name Description ColdFusion The ColdFusion version. Template The requested template. (In the dockable.cfm format, this appears in the Page Overview section and is called Page.) TimeStamp The time the request was completed. (In the dockable.cfm format, this appears in the Page Overview section and is called Date.) Locale The locality and language that determines how information is processed, particularly the message language. User Agent The identity of the browser that made the HTTP request. Remote IP The IP address of the client system that made the HTTP request. Host Name The name of the host running the ColdFusion server that executed the request. [...]... Debugger, you must enable debugging in the ColdFusion Administrator ADOBE COLDFUSION 8 371 ColdFusion Developer’s Guide Set up ColdFusion to use the Debugger 1 In the ColdFusion Administrator, select Debugging & Logging > Debugger Settings 2 Enable the Allow Line Debugging option 3 Specify the port to use for debugging if different from the default that appears 4 Specify the maximum number of simultaneous... calls Installing and uninstalling the ColdFusion Debugger To use the ColdFusion Debugger, you must have the following software installed: • Eclipse version 3.1.2, Eclipse version 3.2, or Flex Builder 2 • ColdFusion 8 To install the ColdFusion Debugger, you install the ColdFusion Eclipse plugins For more information, see Installing and Using ColdFusion Setting up ColdFusion to use the Debugger Before... with the cflog tag” on page 256 ADOBE COLDFUSION 8 3 64 ColdFusion Developer’s Guide Entry Meaning Information The Severity specified in the cftrace call web-29 Server thread that executed the code 04/ 01/02 Date the trace was logged 13:21:11 Time the trace was logged MyApp The application name, as specified in a cfapplication tag 501 ms (1st trace)] The time ColdFusion took to process the current request... number you specify is the same port number specified on the Debugger Settings page of ColdFusion Administrator ADOBE COLDFUSION 8 372 ColdFusion Developer’s Guide If you are running the server configuration, ColdFusion writes these debugging parameters to the jvm.config file when you use the Debugger Settings page of the ColdFusion Administrator 12 If you are not running the server configuration and your... ColdFusion For example, if you are running JRun that runs on JRE 1 .4, copy the tools.jar file of JDK 1 .4 to the \lib folder of ColdFusion 13 If you are running the server version of ColdFusion and you specify a JRE version other than JRE 1.6 in the jvm.config file, you must copy the tools.jar file of the JDK version specified in your jvm.config file to the \lib folder of ColdFusion Note: To debug ColdFusion. .. Settings page ADOBE COLDFUSION 8 363 ColdFusion Developer’s Guide • In-line in your application page: When you specify the inline attribute in a cftrace tag, ColdFusion displays the trace output on the page at the cftrace tag location (An inline cftrace tag does not display any output if it is inside a cfsilent tag block.) The cftrace tag executes only if you select Enable Debugging on the ColdFusion Administrator... browser 4 Select Window > Preferences and specify the home page for your debugging session, the extensions of the file types that you can debug, and the variable scopes of the variables to show in the Variables pane Click OK The home page is the page that appears in the Debug Output Buffer pane when you click the Home button in the Debug Output Buffer pane ADOBE COLDFUSION 8 3 74 ColdFusion Developer’s Guide. .. that the line at which ColdFusion shows an unresolved breakpoint is valid, delete the breakpoint and set it again • Invalid - If ColdFusion determines that the CFML that you edit in Eclipse is the same as the CFML in its memory, and that the breakpoint you have set is at an invalid line, the breakpoint appears as a red X • Disabled ADOBE COLDFUSION 8 375 ColdFusion Developer’s Guide Executing code line... 41 3 Managing LDAP Directories 43 4 Building a Search Interface 45 9 Using Verity Search Expressions 48 8 378 Chapter 22: Introduction to Databases and SQL ColdFusion lets you create dynamic applications... the ColdFusion Debugger Adobe ColdFusion provides debugging information for individual pages However, for complex development tasks, you require a robust and interactive debugger ColdFusion provides a line debugger that you can use when developing ColdFusion applications in Eclipse or Adobe Flex Builder You can set breakpoints, step over, into, or out of code, and inspect variables You can also view ColdFusion . extra processing is required to support LDAP. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 350 WDDX ColdFusion supports the cfwddx tag. ColdFusion stores WDDX (Web Distributed Data Exchange). describe how you can use the information they display. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 3 54 General debugging information ColdFusion displays general debugging information. In the. pairs. This guarantees that you will handle the parameters correctly. ADOBE COLDFUSION 8 ColdFusion Developer’s Guide 348 You can also use the SetEncoding function to specify the character encoding