Home » Author Archives: Mahmoud ElSayed

Author Archives: Mahmoud ElSayed

Recycle Bin in Database

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Oracle introduced in database 10g new feature called ‘Recycle Bin’ to store the dropped database objects. If any table is dropped then any associated object to this table such as indexes, constraints and any other dependent object are renamed with a prefix of bin$$. Use of Recycle Bin If user drop an important object accidentally, and he want to get ...

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ADF : Dynamic View Object

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Today I want to write about dynamic view object which allow me to change its data source (SQL query) and attributes at run time. I will use oracle.jbo.ApplicationModule :: createViewObjectFromQueryStmt method to do this issue. I will present how to do this step by step Create View Object and Application Module   1- Right click on Model project and choose ...

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Java Decompiler in JDeveloper

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Java Decompiler is a standalone graphical utility that displays Java source codes of  “.class” files. Below is snapshot of Java Decompiler program You can download this program from here I will illustrate how to use this program as External Tool in Jdeveloper Integration between Java Decompiler and Jdeveloper You can add this program to external programs in Jdeveloper and integrate ...

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Avoid Null Pointer Exception in Java

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Null Pointer Exception is the most common and most annoying exception in Java. In this post I want to avoid this undesired exception. First let’s create example that raise Null Pointer Exception private Boolean isFinished(String status) { if (status.equalsIgnoreCase("Finish")) { return Boolean.TRUE; } else { return Boolean.FALSE; } } In previous method if we pass the value of “status” variable ...

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