From d179823a2a96d721f3b09efbf925ebd69667e3a9 Mon Sep 17 00:00:00 2001
From: Looly <loolly@aliyun.com>
Date: Sat, 29 Jul 2023 13:05:39 +0800
Subject: [PATCH] =?UTF-8?q?UrlResource=E5=A2=9E=E5=8A=A0size=E6=96=B9?=
 =?UTF-8?q?=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 CHANGELOG.md                                  |  1 +
 .../hutool/core/io/resource/UrlResource.java  | 16 +++++--
 .../java/cn/hutool/core/util/URLUtil.java     | 47 +++++++++++++++++++
 3 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 31e482d9f..ab0a72311 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@
 * 【core  】      ZipReader增加setMaxSizeDiff方法，自定义或关闭ZipBomb（issue#3018@Github）
 * 【db    】      Query.of(entity)构建时传入fields（issue#I7M5JU@Gitee）
 * 【db    】      clickhouse驱动名称变更为com.clickhouse.jdbc.ClickHouseDriver（issue#3224@Github）
+* 【core  】      UrlResource增加size方法（issue#3226@Github）
 
 ### 🐞Bug修复
 * 【core  】      修复MapUtil工具使用filter方法构造传入参数结果问题（issue#3162@Github）
diff --git a/hutool-core/src/main/java/cn/hutool/core/io/resource/UrlResource.java b/hutool-core/src/main/java/cn/hutool/core/io/resource/UrlResource.java
index 21f24b2ef..ab65a9070 100755
--- a/hutool-core/src/main/java/cn/hutool/core/io/resource/UrlResource.java
+++ b/hutool-core/src/main/java/cn/hutool/core/io/resource/UrlResource.java
@@ -1,14 +1,14 @@
 package cn.hutool.core.io.resource;
 
 import cn.hutool.core.io.FileUtil;
+import cn.hutool.core.io.IORuntimeException;
 import cn.hutool.core.util.ObjectUtil;
 import cn.hutool.core.util.URLUtil;
 
-import java.io.File;
-import java.io.InputStream;
-import java.io.Serializable;
+import java.io.*;
 import java.net.URI;
 import java.net.URL;
+import java.net.URLConnection;
 
 /**
  * URL资源访问类
@@ -104,4 +104,14 @@ public class UrlResource implements Resource, Serializable{
 	public String toString() {
 		return (null == this.url) ? "null" : this.url.toString();
 	}
+
+	/**
+	 * 获取资源长度
+	 *
+	 * @return 资源长度
+	 * @since 5.8.21
+	 */
+	public long size() {
+		return URLUtil.size(this.url);
+	}
 }
diff --git a/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java b/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java
index fde460ff2..a66463e67 100644
--- a/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java
@@ -776,4 +776,51 @@ public class URLUtil extends URLEncodeUtil {
 
 		return builder.toString();
 	}
+
+	/**
+	 * 获取URL对应数据长度
+	 * <ul>
+	 *     <li>如果URL为文件，转换为文件获取文件长度。</li>
+	 *     <li>其它情况获取{@link URLConnection#getContentLengthLong()}</li>
+	 * </ul>
+	 *
+	 * @param url URL
+	 * @return 长度
+	 * @since 6.0.0
+	 */
+	public static long size(final URL url) {
+		if (URLUtil.isFileURL(url)) {
+			// 如果资源以独立文件形式存在，尝试获取文件长度
+			final File file = FileUtil.file(url);
+			final long length = file.length();
+			if (length == 0L && !file.exists()) {
+				throw new IORuntimeException("File not exist or size is zero!");
+			}
+			return length;
+		} else {
+			// 如果资源打在jar包中或来自网络，使用网络请求长度
+			// issue#3226, 来自Spring的AbstractFileResolvingResource
+			try {
+				final URLConnection con = url.openConnection();
+				useCachesIfNecessary(con);
+				if (con instanceof HttpURLConnection) {
+					final HttpURLConnection httpCon = (HttpURLConnection) con;
+					httpCon.setRequestMethod("HEAD");
+				}
+				return con.getContentLengthLong();
+			} catch (final IOException e) {
+				throw new IORuntimeException(e);
+			}
+		}
+	}
+
+	/**
+	 * 如果连接为JNLP方式，则打开缓存
+	 *
+	 * @param con {@link URLConnection}
+	 * @since 6.0.0
+	 */
+	public static void useCachesIfNecessary(final URLConnection con) {
+		con.setUseCaches(con.getClass().getSimpleName().startsWith("JNLP"));
+	}
 }