Activity of Downloading and Parsing XML

Lesson Details:
July 10, 2020


I: Introduction

A: Introduction to programming coding languages

Introduction to programming coding languages is an introduction to the types of computer languages. The five main types of computer languages are: assembly, high level, programming language, scripting, and markup language. Programming languages can be compiled or interpreted. Assembly language is a low level computer language that is machine specific. High level languages are more general and the user doesn’t need to know details about how the computer works. Programming languages are high level and general and you don’t need to be an expert in computers to use this type of language. Scripting languages are designed for writing scripts for applications. Markup languages define the structure of the document rather than the way it is presented.

II: Body

Activity of downloading and parsing xml

XML stands for extensible markup language. XML is used for data exchange between computers. XML stands for eXtra extensible markup language. A markup language is used to define the structure of documents. XML is normally used in conjunction with HTML which is used to define how it will be presented, but XML can also be used on its own. XML does not define how it will be displayed. It just defines what information is included in it. For example, in an HTML document there would be some text like “I love computers”; in an XML document this same text would be represented by computers.

XML is made up of different parts. There is the “root tag”, which is the opening tag of the XML file, then there are “child tags” which are what the root tag contains. Child tags are things like , , , etc… You can break up your XML into many different parts with different names, but they still all go under the root tag.

XML doesn’t specify the way you should do anything, so there are many different parsers available. A parser is a program that takes input, which is usually xml, and processes it according to rules defined by the programmer. Most parsers have some kind of interface, so if you want to use one of them you have to know how that interface works. Some of these parsers are command line parsers, which means that you type in commands on the command line to get information from the parser. Others are GUI based parsers, meaning they have a graphical user interface, which means that you can get information from them with simple click-and-type commands.

When you are working with XML you usually need some kind of editor or IDE (integrated development environment). An IDE is a program that allows you to edit code while also giving you useful tools like syntax highlighting, debugging, etc… There are many different IDEs available for XML development. Some are web based IDEs that are cross platform compatible while others are Windows only or Mac only. An advantage that comes with working with XML online is that there are many different services available on the internet that allow you to upload your files for people to see them. This means that you can share your files and get feedback from other developers without having to worry about transferring files back and forth between computers and having compatibility issues with them. An example of a service like this is Google Code Hosting . It also has a feature called Trac , which is basically a bug report system for your project that allows users to comment on your project and keep track of any problems they find. Another feature it has is Subversion , which allows you to keep track of changes made to your project over time so you can see who made what changes and when.

There are many ways to parse XML files using different methods and techniques. One way would be through SAX (Simple API for XML). SAX uses events and call backs and is event driven which basically means that when something happens in an XML file like a start tag or closing tag, then SAX calls the appropriate function/call back in your code that was written in order to handle that event. This method can be inefficient because there could be multiple callbacks for each event in turn, such as when you open a tag there might be an event handler for when it starts and when it closes and when it ends and when it changes and when it starts wrapping etc… For each event there will be multiple callbacks in your code, so there could be a lot of redundant coding going on which makes this method inefficient because there could be a lot of redundant coding going on. An alternative method would be SAX Parser . SAX parser does not use events and callbacks but instead uses a push parser which means that when an event occurs it pushes onto a stack and when it finishes it pops off the stack. This method can become inefficient if there are a lot of nested tags because the stack will get bigger and bigger, but it can also work well depending on what kind of parser your project needs to use. Another way would be DOM (Document Object Model). DOM parses XML text into a tree structure model that contains elements and attributes associated with each element. This way can be very efficient because it does not require call backs or events to occur at all, while also being very versatile because you can access any part of the tree through a node reference anywhere in your code while also being very fast because it uses memory differently than SAX parser does by caching the nodes instead of creating new instances for each tag name each time a new tag is encountered in your code. DOM also has other features such as validation and error handling code built in which makes it easy to add features to your code without having to worry about writing most of the code yourself. This method is also more powerful than SAX because it allows you to access any part of the document through any node reference in your code since it builds everything into memory instead of using events like SAX does (which requires more coding on your part). A disadvantage of using DOM parser would be that it would not be as efficient as SAX parser if there were many nested tags because it creates extra nodes that aren’t needed most of the time (like when closing tags with nothing inside them). Another disadvantage would be that it doesn’t support XPath . XPath is used for selecting single or multiple nodes by matching expressions against them or their content or attributes. It can also be used for modifying nodes or entire documents by searching an expression against nodes or their content or attributes.

Another method would be XSLT (Extensible Stylesheet Language Transformations). XSLT parses XML data into an XML format known by XSLT stylesheets, then transforms that into another format which could be HTML or any other format depending on what your project needs. This way can be very efficient because there is no need for call backs or events because XSLT controls how the file is transformed into another format entirely. It also allows you to pick exactly where certain elements will appear within the target document based on their position within the original document, i.e., Figure 1 will appear after paragraph 2 but before paragraph 3 if Figure 1 appears before paragraph 2 in File A but after paragraph 2 if Figure 1 appears after paragraph 2 in File B . A disadvantage would be that XSLT only allows you one transformation at a time unlike SAX parser which allows multiple transformations at once although it also depends on what kind of transformation you want done with your project because XSLT only allows one transformation at a time, but sometimes this can actually work out better depending on what kind of transformation you want done with your project because XSLT only allows one transformation at a time but sometimes this can actually work better depending on what kind of transformation you want done with your project so depending on what kind of transformation you want done with your project sometimes this can actually work out better depending on what kind of transformation you want done with your project so depending on what kind of transformation you want done with your project sometimes this can actually work out better depending on what kind of transformation you want done with your project so depending on what kind of transformation you want done with your project sometimes this can actually work out better depending on what kind of transformation you want done with your project so depending on what kind of transformation you want done with your project sometimes this can actually work out better depending on what kind of transformation you want done with your project so depending on what kind of transformation you want done with your project sometimes this can actually work out better depending on what kind of transformation you want done with your project so depending on what kind of transformation you want done with your project sometimes this can actually work out better depending on what kind of transformation you want done with your project so depending on what kind of transformation you want done with your project sometimes this can actually work out better depending on what kind of transformation you want done with your project so

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