Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>Have you given any thought to a <code>try{} catch(NullPointerException e){}</code> block? It might feel less elegant, but it will stop your code if any of the method calls fails because the previous one returned <code>null</code>, and it will give you the chance to give the default value if it is null.</p> <p>Another option would be something like this:</p> <pre><code>Something v = /*Default Value*/ // Will be overwritten if subsequent methods succeed. Object temp = a.getB(); // Use whatever Object type getB() returns. if(temp != null){ temp = temp.getC(); /* If getC() returns a different type of object, * either use a different variable or make the temp variable even broader * (such as the generic Object type) */ if(temp != null){ temp = temp.getD(); if(temp != null){ temp = temp.getE(); if(temp != null) v = temp; /* If all previous calls returned something substantial, * v will be something useful */ }//if(getE() != null) }//if(getD() != null) }//if(getC() != null) }//if(getB() != null) </code></pre> <p>If you want, you could use a slightly less CPU efficient, but easier to read, version by not nesting the if statements. If all of the if statements are executed after eachother, a single null will prevent all of the next statements from executing, although its value will still be checked every time.</p> <p>As far as generating these statements, I'm not really sure. That will really depend on how far in advance you can predict what new methods will be available from the <code>Object</code> returned by previous method calls. If you're aiming for auto-generation of code, you might be better off with my first suggestion: <code>try-catch</code></p>
    singulars
    1. This table or related slice is empty.
    1. POeclipse autogenerates !=null recursive calls
      singulars
      1. PTQuestion
    1. PTAnswer
    1. This table or related slice is empty.
    1. USStspurg
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POeclipse autogenerates !=null recursive calls
      singulars
      1. PTQuestion
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTAcceptedByOriginator
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COyes, do a try-catch as you suggested was the other way round: it's easier to do, though I don't like to raise exceptions that could have been controlled in another way. I finished off refactoring all the methods manually, as eclipse doesn't offer such a refactoring possibility.
      singulars
      1. PO
      1. USJayZee
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload