java js前端请求后台去获得音频流,然后播放音乐,音乐可以控制进度,显示总时长

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java js前端请求后台去获得音频流,然后播放音乐,音乐可以控制进度,显示总时长,第1张

AudioCLip主要的方法有:play()播放依次声音;loop()循环播放音乐;stop()停止播放。做法一:InputStreamis=nullAudioStreamas=nullis=getClass().getResourceAsStream("a.wav")try{as=newAudioStream(is)}catch(IOExceptione){}AudioPlayer.player.start(as)此方法将音乐文件放入流中在播放,仅限于JavaApplication,容易报错,空指针异常,或者是流异常,不推荐。做法二:Stringmusic="a.wav"AudioClipclip=Applet.newAudioClip(getClass().getResource(music))次方法在Applet中运行没有问题,但是Application中getclass()会返回空指针,导致失败。推荐做法:privateURLurlprivateAudioClipacFilef1=newFile("C:/3.wav")try{url=f1.toURL()}catch(MalformedURLExceptione){//TODOAuto-generatedcatchblocke.printStackTrace()}ac=Applet.newAudioClip(cb1)ac.play()

一般插件只支持MP3,鱼和熊掌很难兼得,如果考虑浏览器兼容性,那用flash无疑是最好,如果考虑格式的兼容性,则支持html5的浏览器直接用audio标签最好。这个确实是棘手的问题,百度是进行了判断来播放的。我们这因为技术有限,后台进行了转码,推荐你看看jplayer和flowplayer,这两个是比较常见的开源音频插件,但不幸的是都只支持MP3格式

axios

基于 Promise 的 HTTP 请求客户端,可同时在浏览器和 node.js 中使用

功能特性

在浏览器中发送 XMLHttpRequests 请求

在 node.js 中发送 http请求

支持 Promise API

拦截请求和响应

转换请求和响应数据

自动转换 JSON 数据

客户端支持保护安全免受 XSRF 攻击

安装

使用 bower:

$ bower install axios

使用 npm:

$ npm install axios

例子

发送一个 GET 请求

// Make a request for a user with a given ID

axios.get('/user?ID=12345')

.then(function (response) {

console.log(response)

})

.catch(function (response) {

console.log(response)

})// Optionally the request above could also be done as

axios.get('/user', {

params: {

ID: 12345

}

})

.then(function (response) {

console.log(response)

})

.catch(function (response) {

console.log(response)

})发送一个 POST 请求

axios.post('/user', {

firstName: 'Fred',

lastName: 'Flintstone'

})

.then(function (response) {

console.log(response)

})

.catch(function (response) {

console.log(response)

})发送多个并发请求

function getUserAccount() {

return axios.get('/user/12345')

}

function getUserPermissions() {

return axios.get('/user/12345/permissions')

}

axios.all([getUserAccount(), getUserPermissions()])

.then(axios.spread(function (acct, perms) {

// Both requests are now complete

}))axios API

可以通过给 axios传递对应的参数来定制请求:

axios(config)

// Send a POST requestaxios({ method: 'post', url: '/user/12345',

data: {firstName: 'Fred',lastName: 'Flintstone' }})

axios(url[, config])

// Sned a GET request (default method)

axios('/user/12345')

请求方法别名

为方便起见,我们为所有支持的请求方法都提供了别名

axios.get(url[, config])

axios.delete(url[, config])

axios.head(url[, config])

axios.post(url[, data[, config]])

axios.put(url[, data[, config]])

axios.patch(url[, data[, config]])注意

当使用别名方法时, url、 method 和 data 属性不需要在 config 参数里面指定。

并发

处理并发请求的帮助方法

axios.all(iterable)

axios.spread(callback)

创建一个实例

你可以用自定义配置创建一个新的 axios 实例。

axios.create([config])

var instance = axios.create({

baseURL: 'https://some-domain.com/api/',

timeout: 1000,

headers: {'X-Custom-Header': 'foobar'

}})实例方法

所有可用的实例方法都列在下面了,指定的配置将会和该实例的配置合并。

axios#request(config)

axios#get(url[, config])

axios#delete(url[, config])

axios#head(url[, config])

axios#post(url[, data[, config]])

axios#put(url[, data[, config]])

axios#patch(url[, data[, config]])请求配置

下面是可用的请求配置项,只有 url 是必需的。如果没有指定 method ,默认的请求方法是 GET。

{

// `url` is the server URL that will be used for the request

url: '/user',

// `method` is the request method to be used when making the request

method: 'get', // default

// `baseURL` will be prepended to `url` unless `url` is absolute.

// It can be convenient to set `baseURL` for an instance of axios to pass relative URLs

// to methods of that instance.

baseURL: 'https://some-domain.com/api/',

// `transformRequest` allows changes to the request data before it is sent to the server

// This is only applicable for request methods 'PUT', 'POST', and 'PATCH'

// The last function in the array must return a string or an ArrayBuffer

transformRequest: [function (data) {

// Do whatever you want to transform the data

return data

}],

// `transformResponse` allows changes to the response data to be made before

// it is passed to then/catch

transformResponse: [function (data) {

// Do whatever you want to transform the data

return data

}],

// `headers` are custom headers to be sent

headers: {'X-Requested-With': 'XMLHttpRequest'},

// `params` are the URL parameters to be sent with the request

params: {

ID: 12345

},

// `paramsSerializer` is an optional function in charge of serializing `params`

// (e.g. https://www.npmjs.com/package/qs, http://api.jquery.com/jquery.param/)

paramsSerializer: function(params) {

return Qs.stringify(params, {arrayFormat: 'brackets'})

},

// `data` is the data to be sent as the request body

// Only applicable for request methods 'PUT', 'POST', and 'PATCH'

// When no `transformRequest` is set, must be a string, an ArrayBuffer or a hash

data: {

firstName: 'Fred'

},

// `timeout` specifies the number of milliseconds before the request times out.

// If the request takes longer than `timeout`, the request will be aborted.

timeout: 1000,

// `withCredentials` indicates whether or not cross-site Access-Control requests

// should be made using credentials

withCredentials: false, // default

// `adapter` allows custom handling of requests which makes testing easier.

// Call `resolve` or `reject` and supply a valid response (see [response docs](#response-api)).

adapter: function (resolve, reject, config) {

/* ... */

},

// `auth` indicates that HTTP Basic auth should be used, and supplies credentials.

// This will set an `Authorization` header, overwriting any existing

// `Authorization` custom headers you have set using `headers`.

auth: {

username: 'janedoe',

password: 's00pers3cret'

}

// `responseType` indicates the type of data that the server will respond with

// options are 'arraybuffer', 'blob', 'document', 'json', 'text'

responseType: 'json', // default

// `xsrfCookieName` is the name of the cookie to use as a value for xsrf token

xsrfCookieName: 'XSRF-TOKEN', // default

// `xsrfHeaderName` is the name of the http header that carries the xsrf token value

xsrfHeaderName: 'X-XSRF-TOKEN', // default

// `progress` allows handling of progress events for 'POST' and 'PUT uploads'

// as well as 'GET' downloads

progress: function(progressEvent) {

// Do whatever you want with the native progress event

}

}响应的数据结构

响应的数据包括下面的信息:

{

// `data` is the response that was provided by the server

data: {},

// `status` is the HTTP status code from the server response

status: 200,

// `statusText` is the HTTP status message from the server response

statusText: 'OK',

// `headers` the headers that the server responded with

headers: {},

// `config` is the config that was provided to `axios` for the request

config: {}

}当使用 then 或者 catch 时, 你会收到下面的响应:

axios.get('/user/12345')

.then(function(response) {

console.log(response.data)

console.log(response.status)

console.log(response.statusText)

console.log(response.headers)

console.log(response.config)

})默认配置

你可以为每一个请求指定默认配置。

全局 axios 默认配置

axios.defaults.baseURL = 'https://api.example.com'

axios.defaults.headers.common['Authorization'] = AUTH_TOKEN

axios.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded'自定义实例默认配置

// Set config defaults when creating the instance

var instance = axios.create({

baseURL: 'https://api.example.com'

})

// Alter defaults after instance has been created

instance.defaults.headers.common['Authorization'] = AUTH_TOKEN配置的优先顺序

Config will be merged with an order of precedence. The order is library defaults found in lib/defaults.js, then defaults property of the instance, and finally config argument for the request. The latter will take precedence over the former. Here's an example.

// Create an instance using the config defaults provided by the library

// At this point the timeout config value is `0` as is the default for the libraryvar instance = axios.create()

// Override timeout default for the library

// Now all requests will wait 2.5 seconds before timing outinstance.defaults.timeout = 2500

// Override timeout for this request as it's known to take a long timeinstance.get('

/longRequest', { timeout: 5000})拦截器

你可以在处理 then 或 catch 之前拦截请求和响应

// 添加一个请求拦截器

axios.interceptors.request.use(function (config) {

// Do something before request is sent

return config

}, function (error) {

// Do something with request error

return Promise.reject(error)

})

// 添加一个响应拦截器

axios.interceptors.response.use(function (response) {

// Do something with response data

return response

}, function (error) {

// Do something with response error

return Promise.reject(error)

})移除一个拦截器:

var myInterceptor = axios.interceptors.request.use(function () {/*...*/})

axios.interceptors.request.eject(myInterceptor)你可以给一个自定义的 axios 实例添加拦截器:

var instance = axios.create()

instance.interceptors.request.use(function () {/*...*/})错误处理

axios.get('/user/12345')

.catch(function (response) {

if (response instanceof Error) {

// Something happened in setting up the request that triggered an Error

console.log('Error', response.message)

} else {

// The request was made, but the server responded with a status code

// that falls out of the range of 2xx

console.log(response.data)

console.log(response.status)

console.log(response.headers)

console.log(response.config)

}

})Promises

axios 依赖一个原生的 ES6 Promise 实现,如果你的浏览器环境不支持 ES6 Promises,你需要引入 polyfill