read pdf to excel java

convert pdf to excel java source code

extract images from pdf java pdfbox, text to pdf conversion in java, convert pdf to excel in java, convert pdf to image in java, convert pdf to jpg using java, convert pdf to word java, how to generate pdf report in jsp, convert xlsx to pdf using java, convert html image to pdf using itext in java, word to pdf converter java source code, edit pdf using itext in java, merge multiple pdf files into one using java, how to check if a pdf is password protected in java, how to print pdf file without preview using java, java ocr pdf example, itext pdf java new page, how to print data in pdf in java, how to read image from pdf using java, java read pdf and find text, search text in pdf file using java, java itext pdf remove text, free java pdf viewer, how to write byte array to pdf in java, how to add image in pdf using itext in java, java itext add text to pdf, java itext pdf remove text, replace text in pdf using java

Not only is it ugly, but we have to replace all our object initializers to refer to our new RealName property, so it is making us do unnecessary work, which is never good:

class Program Formal parameters { static void MyMethod( MyClass f1, int f2 ) { f1.Val = f1.Val + 5; // Add 5 to field of f1 param. f2 = f2 + 5; // Add 5 to second param. } static void Main( ) { MyClass A1 = new MyClass(); int A2 = 10; MyMethod( A1, A2 ); Actual parameters // Call the method.

Firefighter joe = new Firefighter { RealName = "Joe" };

Are you feeling uncomfortable with this approach yet Let s push on with it just a little bit further, and see what happens if we want to support a second behavior. Say we had a SalariedPerson abstract base that provides us with the contract for getting/setting a person s salary. We re going to need to apply that to both the FirefighterBase and the Administrator, to tie in with the billing system:

abstract class SalariedPerson { public abstract decimal Salary { get; set; } }

We re providing a decimal property for the Salary that must be implemented by any SalariedPerson. So, what happens if we now try to derive from this class for our Administrator, as shown in Example 4-19

Figure 5-7 illustrates the following about the values of the actual and formal parameters at various stages in the execution of the method: Before the method call, variables A1 and A2, which will be used as the actual parameters, are already on the stack. By the beginning of the method, the system has allocated space on the stack for the formal parameters, and copied the values from the actual parameters. Since A1 is a reference type, the reference is copied, resulting in both the actual and formal parameters referring to the same object in the heap. Since A2 is a value type, the value is copied, producing an independent data item. At the end of the method, both f2 and the field of object f1 have been incremented by 5. After method execution, the formal parameters are popped off the stack. The value of A2, the value type, is unaffected by the activity in the method. The value of A1, the reference type, however, has been changed by the activity in the method.

class Administrator : NamedPerson, SalariedPerson { private decimal salary; public override decimal Salary { get { return salary; } set { salary = value; } } // ... }

Another compiler error:

child(); }

Class 'Administrator' cannot have multiple base classes: 'NamedPerson' and 'SalariedPerson'

This is a pretty fundamental roadblock! You cannot derive your class from more than one base class. When the designers of .NET were thinking about the platform fundamentals, they looked at this issue of multiple inheritance and how they d support it across multiple languages, including C#, VB, and C++. They decided that the C++ approach was too messy and prone to error (particularly when you think about how to resolve members that appear in both base classes with the same signature). The implications of multiple inheritance were probably just too difficult to come to grips with, and therefore were unlikely to bring net productivity gains. With that view prevailing, single inheritance of implementation is baked into the platform.

The second type of parameter is called a reference parameter. When using a reference parameter, you must use the ref modifier in both the declaration and the invocation of the method. The actual parameter must be a variable, which must be assigned to before being used as the actual parameter. If it is a reference type variable, it can be assigned a reference or the value null. For example, the following code illustrates the syntax of the declaration and invocation. Include the ref modifier. void MyMethod( ref int val ) { ... } int y = 1; MyMethod ( ref y ); Include the ref modifier. MyMethod ( ref 3+5 ); Must use a variable.

In more recent interviews, the .NET team has reflected that perhaps there might have been a way of allowing multiple inheritance of implementation, without introducing all the complexity of C++ multiple inheritance. That s the benefit of 20/20 hindsight; we (or our children) will just have to wait until the next platform generation and see how the argument goes then.

So are we really stymied No! While we can t support multiple inheritance of implementation, we can support multiple inheritance of interface.

With our abstract base classes in this example, we re not really trying to provide a base implementation for our objects at all. We re trying to mark them as supporting a particular contract that we can then rely on in our client code. C# provides us with a mechanism for doing exactly that: interface. Let s rewrite our NamedPerson and SalariedPerson classes as interfaces instead, as shown in Example 4-20.

interface INamedPerson { string Name { get; } } interface ISalariedPerson { decimal Salary { get; set; } }

// Error!

tiff to pdf converter free download online, split pdf online2pdf, how to read image from pdf file using java, how to protect pdf file from copying and printing online