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| − | Please [[#Share_a_code_snippet|share your code snippets]]! <br>
| + | * [[EDT:Declaring data|Declaring values of EGL native types]] |
| | | | |
| − | == Declaring data <br> ==
| + | * [[EDT:Working with custom types|Working with custom types]] |
| | | | |
| − | '''Variables'''
| + | * [[EDT:Writing statements|Writing statements]] |
| | | | |
| − | <source lang="java">
| + | * [[EDT:Working with a database|Working with a database]] |
| − | // defaults to 0
| + | |
| − | someVal int;
| + | |
| | | | |
| − | // defaults to null.
| + | * [[EDT:Accessing a service|Accessing a service]] |
| − | someVal int?;
| + | |
| | | | |
| − | // initializes value to 15 (future value can be null).
| + | * [[EDT:Writing a Rich UI application|Writing a Rich UI application]] |
| − | someVal int? = 15;
| + | |
| | | | |
| − | // initializes value to 23.
| + | <br><br> |
| − | someVal int = 23;
| + | |
| | | | |
| − | // defaults to "".
| + | To share a code snippet: |
| − | firstName string;
| + | |
| | | | |
| − | // defaults to null.
| + | *On the page of interest, click '''Edit''' and, if necessary, log in to eclipse.org. |
| − | firstName string?;
| + | *Add a section or update an existing one; but always include your code in the following wikitext markup:<br> |
| | + | <pre> <source lang="java"> |
| | + | // put code here |
| | + | </source> |
| | + | |
| | + | </pre> |
| | + | *The <source> tag is used instead of <code> or <pre> since it provides syntax highlighting similar to an advanced source code editor. We use the Java language highlighting, since a highlighter for EGL doesn't exist (yet). If you are interested in writing a syntax highlighter for EGL, the GeSHi (Generic Syntax Highlighter) extension is used. |
| | + | * For longer examples, consider adding line numbers using line="GESHI_NORMAL_LINE_NUMBERS" in the source tag, though for some reason then the snippet doesn't appear in a colored background. |
| | + | *To add most of your content, click Wikitext or disable the Rich Editor. |
| | + | *Before you create a new page, read [[EDT:How to Create/Edit Wiki pages|these instructions]]. |
| | | | |
| − | // initializes value to "John".
| + | For help with editing, see [http://meta.wikimedia.org/wiki/Help:Wikitext_examples Wikitext examples]. |
| − | firstName string = "John";
| + | |
| − | | + | |
| − | // defaults to 0.
| + | |
| − | largeVal bigint;
| + | |
| − | | + | |
| − | // number with 5 total digits (2 after the decimal point). Defaults to 000.00.
| + | |
| − | amount decimal(5,2);
| + | |
| − | | + | |
| − | // defaults to 0.0. | + | |
| − | coord float;
| + | |
| − | | + | |
| − | // defaults to false | + | |
| − | toggle boolean;
| + | |
| − | | + | |
| − | // defaults to today's date.
| + | |
| − | dob date;
| + | |
| − | | + | |
| − | // defaults to the current timestamp.
| + | |
| − | ts timestamp?;
| + | |
| − | | + | |
| − | // value can be set to any value (primitive, object, etc). See the casting examples later.
| + | |
| − | x any?;
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''Constants'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | // value is unchangeable.
| + | |
| − | const NUMBEROFDAYS int = 7;
| + | |
| − | | + | |
| − | // values are changeable, but name cannot refer to another list.
| + | |
| − | const
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''Arrays'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | | + | |
| − | vals int[]; // new dynamic array of size 0
| + | |
| − | vals int[]?; // dynamic array, but not instantiated (vals must be instantiated before it can be accessed)
| + | |
| − | vals int[] = new int[4]; // new dynamic array of size 4; all values set to their default value (0 in this example)
| + | |
| − | | + | |
| − | names string[] = [ "Paul", "John", "George", "Ringo" ]; // dynamic array, initialized with 4 values
| + | |
| − | names[1] = "Bob"; // assigns the first index in the array to "Bob"
| + | |
| − | names[names.getSize()] = "Ken"; // assigns the last index in the array to "Ken"
| + | |
| − | | + | |
| − | cities string[]; // new dynamic array of size 0
| + | |
| − | cities.appendElement("Delta"); // appends a new value to the end of the array
| + | |
| − | cities.appendAll([ "Denver", "Pueblo" ]); // appends two new values to the end of the array
| + | |
| − | cities.removeElement(2); // removes the second value in the array
| + | |
| − | cities.removeAll(); // removes all values from the array
| + | |
| − | | + | |
| − | </source>
| + | |
| − | | + | |
| − | <br>
| + | |
| − | | + | |
| − | <br>
| + | |
| − | | + | |
| − | == Rich UI ==
| + | |
| − | | + | |
| − | == Services ==
| + | |
| − | | + | |
| − | '''Calling a REST service'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | http HttpRest{request.uri="http:host\\myService"};
| + | |
| − | srvc IRest?;
| + | |
| − | srvc = ServiceLib.completeBind(srvc, http);
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''Accessing HTTP request headers'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | http HttpRest{};
| + | |
| − | http.request.headers = new Dictionary { param1 = "a value to pass to my service" };
| + | |
| − | srvc IRest?{@Resource {}};
| + | |
| − | srvc = ServiceLib.completeBind(srvc, http);
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''HTTP request and response'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | function invokeDoSomething()
| + | |
| − | call srvc.doSomething() returning to serviceCallback;
| + | |
| − | end
| + | |
| − | | + | |
| − | function serviceCallback(returnValueOne String, callbackHttp IHTTP in)
| + | |
| − | // process callback request or response
| + | |
| − | end
| + | |
| − | </source>
| + | |
| − | | + | |
| − | == Database access ==
| + | |
| − | | + | |
| − | '''Defining a record'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | record CUSTOMER type Entity{@table{name = "CUSTOMER"}} // record is bound to the CUSTOMER table (or view)
| + | |
| − | CUSTID string{@id}; // primary key field
| + | |
| − | NAME string;
| + | |
| − | COUNTRY string;
| + | |
| − | STATE string?; // nullable field
| + | |
| − | end
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''Getting a record'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | function getCustomer(someId String in} returns (Customer)
| + | |
| − | ds SQLDataSource?{@resource {}}; // declares a data source that will use binding name "ds" (since a name is not specified)
| + | |
| − | | + | |
| − | aCust Customer; // declares and empty customer record
| + | |
| − | get aCust from ds using(someId); // gets the record in the table that has a key value of someID and populates the customer record
| + | |
| − | | + | |
| − | get aCust from ds using(someId) with #sql{ // alternative approach for getting a single record (allows for customizing the SQL)
| + | |
| − | SELECT *
| + | |
| − | FROM CUSTOMER
| + | |
| − | WHERE id = ?
| + | |
| − | };
| + | |
| − | | + | |
| − | vals Dictionary; // declares a new dictionary
| + | |
| − | get vals from ds using(someId) with #sql{ // alternative approach for getting a single record (does not require a Record definition)
| + | |
| − | SELECT *
| + | |
| − | FROM CUSTOMER
| + | |
| − | WHERE id = ?
| + | |
| − | }; // creates a key/value pair in the dictionary for each column in the result set
| + | |
| − | | + | |
| − | return (aCust);
| + | |
| − | end
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''Getting multiple records''' <source lang="java">
| + | |
| − | function getCustomer(} returns (Customer[])
| + | |
| − | ds SQLDataSource?{@resource {}}; // declares a data source that will use binding name "ds" (since a name is not specified)
| + | |
| − | | + | |
| − | custs Customer[]; // declares a new dynamic array of customer records
| + | |
| − | get custs from ds; // populates the array with a Customer record for each row in the result set
| + | |
| − | | + | |
| − | get custs from ds with #sql {
| + | |
| − | select * from customer where state = 'CO'
| + | |
| − | }; // populates the array, but with a limited set of Customer records
| + | |
| − | | + | |
| − | state String = "CO";
| + | |
| − | get custs from ds using(state) with #sql {
| + | |
| − | select * from customer where state = ?
| + | |
| − | }; // parameterized version of the previous example
| + | |
| − | | + | |
| − | | + | |
| − | end
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''Inserting a record'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | function addCustomer{customer Customer in}
| + | |
| − | ds SQLDataSource?{@resource {}};
| + | |
| − | add customer to ds;
| + | |
| − | end
| + | |
| − | </source>
| + | |
| − | | + | |
| − | '''Looping through a SQL result set'''
| + | |
| − | | + | |
| − | <source lang="java">
| + | |
| − | function loopCust()
| + | |
| − | ds SQLDataSource?{@resource{uri = "binding:myDB" }}; // declares a new data source
| + | |
| − | rs SQLResultSet?; // declares a new result set
| + | |
| − | | + | |
| − | open rs from ds with #sql{ // opens a result set using the specified SQL query
| + | |
| − | SELECT * FROM CUSTOMER
| + | |
| − | };
| + | |
| − | | + | |
| − | myCust Customer;
| + | |
| − | | + | |
| − | //Loop through results and write out customer name
| + | |
| − | while(rs.getNext())
| + | |
| − | get myCust from rs;
| + | |
| − | Syslib.writeStdOut ("Customer name: " + myCust.name);
| + | |
| − | end
| + | |
| − | | + | |
| − | end
| + | |
| − | </source>
| + | |
| − | | + | |
| − | <br>
| + | |
| − | | + | |
| − | == Share a code snippet ==
| + | |
| − | | + | |
| − | Edit this page by logging in to eclipse.org and clicking the Edit tab. Use the Wikitext editor to add a new snippet. Add the title using Heading 4. Use the '''source lang="java"''' tag to provide a background for your snippet and some syntax highlighting.
| + | |
| | | | |
| | [[Category:EDT]] | | [[Category:EDT]] |
