url对象java（js url对象）

今天给各位分享url对象java的知识，其中也会对js url对象进行解释，如果能碰巧解决你现在面临的问题，别忘了关注本站，现在开始吧！

微信号：cloud7591
如需了解更多，欢迎添加客服微信咨询。
复制微信号

本文目录一览：

• 1、java构造方法URL(URL urlobj,String urlSpecifier)是什么意思？
• 2、java中如何根据一个网址获得该网页的源代码？
• 3、关于java调用url接口方法的问题
• 4、java的URL对象是不是只能是一个网站的域名，比如"http://www.baidu.com",而不能是“119.75.217.109”?

java构造方法URL(URL urlobj,String urlSpecifier)是什么意思？

有参构造：

意思是你使用这个构造方法创建对象的时候需要给他传递两个参数。一个参数是URL类型（对象本身的类型），另一个字符串类型。列如 URL rul = new URL(new URL(),"str");

源码：

public URL(URL context, String spec) throws MalformedURLException {

this(context, spec, null);

}

两个参数的构造里调用了三个参数的构造。

具体三参数的构造可以参考源码

/**

* Creates a URL by parsing the given spec with the specified handler

* within a specified context. If the handler is null, the parsing

* occurs as with the two argument constructor.

*

* @param context the context in which to parse the specification.

* @param spec the {@code String} to parse as a URL.

* @param handler the stream handler for the URL.

* @exception MalformedURLException if no protocol is specified, or an

* unknown protocol is found, or {@code spec} is {@code null}.

* @exception SecurityException

* if a security manager exists and its

* {@code checkPermission} method doesn't allow

* specifying a stream handler.

* @see java.net.URL#URL(java.lang.String, java.lang.String,

* int, java.lang.String)

* @see java.net.URLStreamHandler

* @see java.net.URLStreamHandler#parseURL(java.net.URL,

* java.lang.String, int, int)

*/

public URL(URL context, String spec, URLStreamHandler handler)

throws MalformedURLException

{

String original = spec;

int i, limit, c;

int start = 0;

String newProtocol = null;

boolean aRef=false;

boolean isRelative = false;

// Check for permission to specify a handler

if (handler != null) {

SecurityManager sm = System.getSecurityManager();

if (sm != null) {

checkSpecifyHandler(sm);

}

}

try {

limit = spec.length();

while ((limit 0) (spec.charAt(limit - 1) = ' ')) {

limit--; //eliminate trailing whitespace

}

while ((start limit) (spec.charAt(start) = ' ')) {

start++; // eliminate leading whitespace

}

if (spec.regionMatches(true, start, "url:", 0, 4)) {

start += 4;

}

if (start spec.length() spec.charAt(start) == '#') {

/* we're assuming this is a ref relative to the context URL.

* This means protocols cannot start w/ '#', but we must parse

* ref URL's like: "hello:there" w/ a ':' in them.

*/

aRef=true;

}

for (i = start ; !aRef (i limit)

((c = spec.charAt(i)) != '/') ; i++) {

if (c == ':') {

String s = spec.substring(start, i).toLowerCase();

if (isValidProtocol(s)) {

newProtocol = s;

start = i + 1;

}

break;

}

}

// Only use our context if the protocols match.

protocol = newProtocol;

if ((context != null) ((newProtocol == null) ||

newProtocol.equalsIgnoreCase(context.protocol))) {

// inherit the protocol handler from the context

// if not specified to the constructor

if (handler == null) {

handler = context.handler;

}

// If the context is a hierarchical URL scheme and the spec

// contains a matching scheme then maintain backwards

// compatibility and treat it as if the spec didn't contain

// the scheme; see 5.2.3 of RFC2396

if (context.path != null context.path.startsWith("/"))

newProtocol = null;

if (newProtocol == null) {

protocol = context.protocol;

authority = context.authority;

userInfo = context.userInfo;

host = context.host;

port = context.port;

file = context.file;

path = context.path;

isRelative = true;

}

}

if (protocol == null) {

throw new MalformedURLException("no protocol: "+original);

}

// Get the protocol handler if not specified or the protocol

// of the context could not be used

if (handler == null

(handler = getURLStreamHandler(protocol)) == null) {

throw new MalformedURLException("unknown protocol: "+protocol);

}

this.handler = handler;

i = spec.indexOf('#', start);

if (i = 0) {

ref = spec.substring(i + 1, limit);

limit = i;

}

/*

* Handle special case inheritance of query and fragment

* implied by RFC2396 section 5.2.2.

*/

if (isRelative start == limit) {

query = context.query;

if (ref == null) {

ref = context.ref;

}

}

handler.parseURL(this, spec, start, limit);

} catch(MalformedURLException e) {

throw e;

} catch(Exception e) {

MalformedURLException exception = new MalformedURLException(e.getMessage());

exception.initCause(e);

throw exception;

}

}

java中如何根据一个网址获得该网页的源代码？

package test;

import java.io.BufferedReader;

import java.io.InputStreamReader;

import java.net.HttpURLConnection;

import java.net.URL;

public class HttpTest {

private String u;

private String encoding;

public static void main(String[] args) throws Exception {

HttpTest client = new HttpTest("", "UTF-8");

client.run();

}

public HttpTest(String u, String encoding) {

this.u = u;

this.encoding = encoding;

}

public void run() throws Exception {

URL url = new URL(u);// 根据链接（字符串格式），生成一个URL对象

HttpURLConnection urlConnection = (HttpURLConnection) url

.openConnection();// 打开URL

BufferedReader reader = new BufferedReader(new InputStreamReader(

urlConnection.getInputStream(), encoding));// 得到输入流，即获得了网页的内容

String line; // 读取输入流的数据，并显示

while ((line = reader.readLine()) != null) {

System.out.println(line);

}

}

}

根据具体问题类型，进行步骤拆解／原因原理分析／内容拓展等。

具体步骤如下：／导致这种情况的原因主要是……

关于java调用url接口方法的问题

对于具体的数据请求方式、请求方式、响应数据格式要看你的接口要求，这是通用代码:

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.net.HttpURLConnection;

import java.net.URL;

public class Test {

public static void main(String[] args) throws IOException {

System.out.println(getData());

}

public static String getData() throws IOException {

// 创建指定url的url对象,这里的地址是:淘宝商品搜索建议

URL url = new URL(";q=电脑callback=cb");

// 创建http链接对象

HttpURLConnection con = (HttpURLConnection) url.openConnection();

// 设置请求方式

con.setRequestMethod("POST");

// 打开链接,上一步和该步骤作用相同，可以省略

con.connect();

// 获取请求返回内容并设置编码为UTF-8

BufferedReader reader = new BufferedReader(new InputStreamReader(con.getInputStream(), "UTF-8"));

// 将返回数据拼接为字符串

StringBuffer sb = new StringBuffer();

// 临时字符串

String temp = null;

// 获取数据

while ((temp = reader.readLine()) != null) {

sb.append(temp);

}

// 关闭流

reader.close();

return sb.toString();

}

}

结果:

java的URL对象是不是只能是一个网站的域名，比如"http://www.baidu.com",而不能是“119.75.217.109”?

URL myWeb=new URL(" ");

"" 可以写成""

ip比域名更快点（省去域名解析）

我的猜想是：你的URL格式没写正确。

url对象java的介绍就聊到这里吧，感谢你花时间阅读本站内容，更多关于js url对象、url对象java的信息别忘了在本站进行查找喔。