Home Java javaTutorial Detailed introduction to Ajax cross-domain calling JAVA background

Detailed introduction to Ajax cross-domain calling JAVA background

May 28, 2017 am 09:26 AM

This article mainly introduces the detailed explanation of Ajax cross-domain (jsonp) calling JAVA background. The editor thinks it is quite good. Now I will share it with you and make it for everyone. refer to. Let’s follow the editor to take a look

1. JSONP definition

JSONP is the abbreviation of English JSON with Padding, which is a Unofficial protocol. It allows script tags to be generated on the server side and returned to the client, enabling site access in the form of javascript callback. JSONP is a script tag injection that adds the response returned by the server to the page to implement specific functions.

2. The origin of JSONP

To explain the origin of JSONP, first let’s talk about the browser’s “SOP: Same Origin Policy”. In short, the browser restricts script programs to only interact with scripts of the same protocol, same domain name, and same port. This includes sharing and passing variables, etc. The delivery of cookie also follows the same strategy. This causes some troubles when integrating applications involving multiple servers. The problem of cross-domain access causes the Ajax code of site A to be unable to access the data of site B.

How to solve cross-domain access? Then you need to take advantage of a feature of the browser: although the browser does not allow scripts in the page to read data across domains, it allows HTML to reference cross-domain resources, such as pictures , CSS and scripts. The reference to the script program is special. After it is parsed by the browser, it is the same as the local script program and can be interpreted and executed immediately. For example, in a js file on site B, a simple prompt box: alert ("This is Victor!");. If you reference this js on site A, the script will be executed in the application on site B and display an alert message. Since the reference of off-site scripts is implemented through script tags, and the script program can control all tags of the HTML page through DOM (including dynamically creating script tags), this can be achieved by calling off-site programs. Changes were made to local resources. In addition, through the use of

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Perfect Number in Java Perfect Number in Java Aug 30, 2024 pm 04:28 PM

Guide to Perfect Number in Java. Here we discuss the Definition, How to check Perfect number in Java?, examples with code implementation.

Weka in Java Weka in Java Aug 30, 2024 pm 04:28 PM

Guide to Weka in Java. Here we discuss the Introduction, how to use weka java, the type of platform, and advantages with examples.

Smith Number in Java Smith Number in Java Aug 30, 2024 pm 04:28 PM

Guide to Smith Number in Java. Here we discuss the Definition, How to check smith number in Java? example with code implementation.

Java Spring Interview Questions Java Spring Interview Questions Aug 30, 2024 pm 04:29 PM

In this article, we have kept the most asked Java Spring Interview Questions with their detailed answers. So that you can crack the interview.

Break or return from Java 8 stream forEach? Break or return from Java 8 stream forEach? Feb 07, 2025 pm 12:09 PM

Java 8 introduces the Stream API, providing a powerful and expressive way to process data collections. However, a common question when using Stream is: How to break or return from a forEach operation? Traditional loops allow for early interruption or return, but Stream's forEach method does not directly support this method. This article will explain the reasons and explore alternative methods for implementing premature termination in Stream processing systems. Further reading: Java Stream API improvements Understand Stream forEach The forEach method is a terminal operation that performs one operation on each element in the Stream. Its design intention is

TimeStamp to Date in Java TimeStamp to Date in Java Aug 30, 2024 pm 04:28 PM

Guide to TimeStamp to Date in Java. Here we also discuss the introduction and how to convert timestamp to date in java along with examples.

Java Program to Find the Volume of Capsule Java Program to Find the Volume of Capsule Feb 07, 2025 am 11:37 AM

Capsules are three-dimensional geometric figures, composed of a cylinder and a hemisphere at both ends. The volume of the capsule can be calculated by adding the volume of the cylinder and the volume of the hemisphere at both ends. This tutorial will discuss how to calculate the volume of a given capsule in Java using different methods. Capsule volume formula The formula for capsule volume is as follows: Capsule volume = Cylindrical volume Volume Two hemisphere volume in, r: The radius of the hemisphere. h: The height of the cylinder (excluding the hemisphere). Example 1 enter Radius = 5 units Height = 10 units Output Volume = 1570.8 cubic units explain Calculate volume using formula: Volume = π × r2 × h (4

PHP vs. Python: Understanding the Differences PHP vs. Python: Understanding the Differences Apr 11, 2025 am 12:15 AM

PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries.

See all articles