Java URL 编码 : URLEncoder vs. URI

Question

查看 W3 Schools URL encoding webpage ，它说 @ 应该编码为 %40，而 space 应该编码为 %20。

URLEncoder 和 URI 我都试过了，但是上面的都没有:

import java.net.URI;
import java.net.URLEncoder;

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

        // Prints me%40home.com (CORRECT)
        System.out.println(URLEncoder.encode("me@home.com", "UTF-8"));

        // Prints Email+Address (WRONG: Should be Email%20Address)
        System.out.println(URLEncoder.encode("Email Address", "UTF-8"));

        // http://www.home.com/test?Email%20Address=me@home.com
        // (WRONG: it has not encoded the @ in the email address)
        URI uri = new URI("http", "www.home.com", "/test", "Email Address=me@home.com", null);
        System.out.println(uri.toString());
    }
}

出于某种原因，URLEncoder 正确输入电子邮件地址但不输入空格，URI 正确输入货币但不输入电子邮件地址。

我应该如何对这两个参数进行编码以与 w3schools 所说的正确(或者 w3schools 错误？)一致

Answer 1

虽然我认为来自@fge 的答案是正确的，因为我使用的是依赖于 W3Schools 文章中概述的编码的第 3 方网络服务，但我遵循了来自 Java equivalent to JavaScript's encodeURIComponent that produces identical output? 的答案。

public static String encodeURIComponent(String s) {
    String result;

    try {
        result = URLEncoder.encode(s, "UTF-8")
                .replaceAll("\\+", "%20")
                .replaceAll("\\%21", "!")
                .replaceAll("\\%27", "'")
                .replaceAll("\\%28", "(")
                .replaceAll("\\%29", ")")
                .replaceAll("\\%7E", "~");
    } catch (UnsupportedEncodingException e) {
        result = s;
    }

    return result;
}