Tutorial by Examples

Here we have a class and we want the identity field (userUid) to have its value generated via a SEQUENCE in the database. This SEQUENCE is assumed to be called USER_UID_SEQ, and can be created by a DBA, or can be created by the JPA provider. @Entity @Table(name="USER") public class User...

For the distressed user, vim provides words of wisdom. :help!

Iterator methods can be broken into two distinct groups: Adapters Adapters take an iterator and return another iterator // Iterator Adapter // | | let my_map = (1..6).map(|x| x * x); println!("{:?}", my_map); Output Map { iter: 1..6 } Note that the v...

If you want to remove calls to certain methods, assuming they return void and have no side affects (as in, calling them doesn't change any system values, reference arguments, statics, etc.) then you can have ProGuard remove them from the output after the build is complete. For example, I find this ...

For functions that need to take a collection of objects, slices are usually a good choice: fn work_on_bytes(slice: &[u8]) {} Because Vec<T> and arrays [T; N] implement Deref<Target=[T]>, they can be easily coerced to a slice: let vec = Vec::new(); work_on_bytes(&vec); le...

The following output equivalent results: class IfElseExample { public string DebugToString(object a) { if (a is StringBuilder) { return DebugToStringInternal(a as StringBuilder); } else if (a is List<string>) { ...

template <div id="demo">{{fullName}}</div> watch example var vm = new Vue({ el: '#demo', data: { firstName: 'Foo', lastName: 'Bar', fullName: 'Foo Bar' } }) vm.$watch('firstName', function (val) { this.fullName = val + ' ' + this.lastName })...

This example portrays the most simple ALV creation using the cl_salv_table class and no additional formatting options. Additional formatting options would be included after the TRY ENDTRY block and before the alv->display( ) method call. All subsequent examples using the ABAP Objects approach to...

This example shows how to optimize the column width so that column headings and data are not chopped off. alv->get_columns( )->set_optimize( ).

This example hides the MANDT (client) field from the ALV. Note that the parameter passed to get_column( ) must be capitalized in order for this to work. alv->get_columns( )->get_column( 'MANDT' )->set_visible( if_salv_c_bool_sap=>false ).

The column text may change upon the horizontal resizing of a column. There are three methods to accomplish this: Method NameMaximum Length of Headingset_short_text10set_medium_text20set_long_text40 The following example shows usage of all three. A column object is declared and instantiated as a re...

The following method call enables usage of many advanced features such as sorting, filtering, and exporting data. alv->get_functions( )->set_all( ).

This method increases readability by giving consecutive rows alternating background color shading. alv->get_display_settings( )->set_striped_pattern( if_salv_c_bool_sap=>true ).

By default, when an ALV is displayed, the title at the top is just the program name. This method allows the user to set a title of up to 70 characters. The following example shows how a dynamic title can be set that displays the number of records displayed. alv->get_display_settings( )->set_l...

Suppose you have a parentView into which you want to insert a new subView programmatically (eg. when you want to insert an UIImageView into a UIViewController's view), than you can do it as below. Objective-C [parentView addSubview:subView]; Swift parentView.addSubview(subView) You can also...

CSS .bordered { border-image: linear-gradient(to right, red 20%, green 20%, green 40%, blue 40%, blue 60%, maroon 60%, maroon 80%, chocolate 80%); /* gradient with required colors */ border-image-slice: 1; } HTML <div class='bordered'>Border on all sides</div> The above ex...

Formats results of SELECT query as JSON text. FOR JSON PATH clause is added after query: SELECT top 3 object_id, name, type, principal_id FROM sys.objects FOR JSON PATH Column names will be used as keys in JSON, and cell values will be generated as JSON values. Result of the query would be an a...

FOR JSON PATH enables you to control format of the output JSON using column aliases: SELECT top 3 object_id as id, name as [data.name], type as [data.type] FROM sys.objects FOR JSON PATH Column alias will be used as a key name. Dot-separated column aliases (data.name and data.type) will be gen...

WITHOUT_ARRAY_WRAPPER option enables you to generate a single object instead of the array. Use this option if you know that you will return single row/object: SELECT top 3 object_id, name, type, principal_id FROM sys.objects WHERE object_id = 3 FOR JSON PATH, WITHOUT_ARRAY_WRAPPER Single obje...

FOR JSON clause ignores NULL values in cells. If you want to generate "key": null pairs for cells that contain NULL values, add INCLUDE_NULL_VALUES option in the query: SELECT top 3 object_id, name, type, principal_id FROM sys.objects FOR JSON PATH, INCLUDE_NULL_VALUES NULL values in...