fix alowPatch

hutool-http/src/main/java/cn/hutool/http/HttpConnection.java

@@ -13,8 +13,6 @@ import javax.net.ssl.SSLSocketFactory;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import java.lang.reflect.Field;
-import java.lang.reflect.Modifier;
 import java.net.HttpURLConnection;
 import java.net.ProtocolException;
 import java.net.Proxy;
@@ -122,7 +120,7 @@ public class HttpConnection {
 
 			// 增加PATCH方法支持
 			if (Method.PATCH.equals(method)) {
-				allowPatch();
+				HttpGlobalConfig.allowPatch();
 			}
 		}
 
@@ -546,23 +544,5 @@ public class HttpConnection {
 	private URLConnection openConnection() throws IOException {
 		return (null == this.proxy) ? url.openConnection() : url.openConnection(this.proxy);
 	}
-
-	/**
-	 * 增加支持的METHOD方法
-	 * see: https://stackoverflow.com/questions/25163131/httpurlconnection-invalid-http-method-patch
-	 *
-	 * @since 5.1.6
-	 */
-	private static void allowPatch() {
-		final Field methodsField = ReflectUtil.getField(HttpURLConnection.class, "methods");
-		if (null != methodsField) {
-			// 去除final修饰
-			ReflectUtil.setFieldValue(methodsField, "modifiers", methodsField.getModifiers() & ~Modifier.FINAL);
-			final String[] methods = {
-					"GET", "POST", "HEAD", "OPTIONS", "PUT", "DELETE", "TRACE", "PATCH"
-			};
-			ReflectUtil.setFieldValue(null, methodsField, methods);
-		}
-	}
 	// --------------------------------------------------------------- Private Method end
 }

hutool-http/src/main/java/cn/hutool/http/HttpGlobalConfig.java

@@ -1,10 +1,14 @@
 package cn.hutool.http;
 
-import java.io.Serializable;
+import cn.hutool.core.util.ReflectUtil;
-import java.net.CookieManager;
-
 import cn.hutool.http.cookie.GlobalCookieManager;
 
+import java.io.Serializable;
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+import java.net.CookieManager;
+import java.net.HttpURLConnection;
+
 /**
  * HTTP 全局参数配置
  *
@@ -15,6 +19,7 @@ public class HttpGlobalConfig implements Serializable {
 	private static final long serialVersionUID = 1L;
 
 	protected static int timeout = -1;
+	private static boolean isAllowPatch = false;
 
 	/**
 	 * 获取全局默认的超时时长
@@ -30,7 +35,7 @@ public class HttpGlobalConfig implements Serializable {
 	 *
 	 * @param customTimeout 超时时长
 	 */
-	public static void setTimeout(int customTimeout) {
+	synchronized public static void setTimeout(int customTimeout) {
 		timeout = customTimeout;
 	}
 
@@ -65,4 +70,27 @@ public class HttpGlobalConfig implements Serializable {
 	public static void closeCookie() {
 		GlobalCookieManager.setCookieManager(null);
 	}
+
+	/**
+	 * 增加支持的METHOD方法<br>
+	 * 此方法通过注入方式修改{@link HttpURLConnection}中的methods静态属性，增加PATCH方法<br>
+	 * see: https://stackoverflow.com/questions/25163131/httpurlconnection-invalid-http-method-patch
+	 *
+	 * @since 5.7.4
+	 */
+	synchronized public static void allowPatch() {
+		if(isAllowPatch){
+			return;
+		}
+		final Field methodsField = ReflectUtil.getField(HttpURLConnection.class, "methods");
+		if (null != methodsField) {
+			// 去除final修饰
+			ReflectUtil.setFieldValue(methodsField, "modifiers", methodsField.getModifiers() & ~Modifier.FINAL);
+			final String[] methods = {
+					"GET", "POST", "HEAD", "OPTIONS", "PUT", "DELETE", "TRACE", "PATCH"
+			};
+			ReflectUtil.setFieldValue(null, methodsField, methods);
+			isAllowPatch = true;
+		}
+	}
 }

hutool-http/src/main/java/cn/hutool/http/HttpInputStream.java

@@ -35,6 +35,7 @@ public class HttpInputStream extends InputStream {
 		return this.in.read();
 	}
 
+	@SuppressWarnings("NullableProblems")
 	@Override
 	public int read(byte[] b, int off, int len) throws IOException {
 		return this.in.read(b, off, len);