enjoy 3.3 release ^_^

src/main/java/com/jfinal/template/expr/ast/MethodKeyBuilder.java

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+/**
+ * Copyright (c) 2011-2017, James Zhan 詹波 (jfinal@126.com).
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.jfinal.template.expr.ast;
+
+import com.jfinal.kit.HashKit;
+
+/**
+ * MethodKeyBuilder
+ */
+public abstract class MethodKeyBuilder {
+	
+	/**
+	 * 生成指定 class、指定方法名、指定方法形参类型的 key 值，用于缓存
+	 */
+	public abstract Long getMethodKey(Class<?> targetClass, String methodName, Class<?>[] argTypes);
+	
+	// 默认使用 FastMethodKeyBuilder
+	static MethodKeyBuilder instance = new FastMethodKeyBuilder();
+	
+	public static MethodKeyBuilder getInstance() {
+		return instance;
+	}
+	
+	/**
+	 * 切换到 StrictMethodKeyBuilder
+	 * 
+	 * <pre>
+	 * 特别注意：
+	 *   如果希望将 configEngine(Engine me) 中的 Engine 切换到 StrictMethodKeyBuilder，
+	 *   需要在 YourJFinalConfig extends JFinalConfig 中利用如下代码块才能生效：
+	 * 	  static {
+	 * 			MethodKeyBuilder.useStrictMethodKeyBuilder();
+	 *    }
+	 * 
+	 *   原因是在 com.jfinal.core.Config 中 new Engine() 时 useStrictMethodKeyBuilder()
+	 *   方法并未生效，所以 extension method 生成 method key 时仍然使用的是  FastMethodKeyBuilder
+	 *   以至于在运行时，使用 StrictMethodKeyBuilder 生成的 key 找不到 extension method
+	 * 
+	 * </pre>
+	 */
+	public static void useStrictMethodKeyBuilder() {
+		MethodKeyBuilder.instance = new StrictMethodKeyBuilder();
+	}
+	
+	/**
+	 * 切换到用户自定义 MethodKeyBuilder
+	 */
+	public static void setMethodKeyBuilder(MethodKeyBuilder methodKeyBuilder) {
+		if (methodKeyBuilder == null) {
+			throw new IllegalArgumentException("methodKeyBuilder can not be null");
+		}
+		MethodKeyBuilder.instance = methodKeyBuilder;
+	}
+	
+	/**
+	 * FastMethodKeyBuilder
+	 * 
+	 * targetClass、methodName、argTypes 的 hash 直接使用 String.hashCode()
+	 * String.hashCode() 会被缓存，性能更好
+	 */
+	public static class FastMethodKeyBuilder extends MethodKeyBuilder {
+		public Long getMethodKey(Class<?> targetClass, String methodName, Class<?>[] argTypes) {
+			long hash = HashKit.FNV_OFFSET_BASIS_64;
+			hash ^= targetClass.getName().hashCode();
+			hash *= HashKit.FNV_PRIME_64;
+			
+			hash ^= methodName.hashCode();
+			hash *= HashKit.FNV_PRIME_64;
+			
+			if (argTypes != null) {
+				for (int i=0; i<argTypes.length; i++) {
+					Class<?> type = argTypes[i];
+					if (type != null) {
+						hash ^= type.getName().hashCode();
+						hash *= HashKit.FNV_PRIME_64;
+					}
+				}
+			}
+			return hash;
+		}
+	}
+	
+	/**
+	 * StrictMethodKeyBuilder
+	 * 
+	 * targetClass、methodName、argTypes 三部分全部使用 fnv1a64 算法计算 hash
+	 */
+	public static class StrictMethodKeyBuilder extends MethodKeyBuilder {
+		public Long getMethodKey(Class<?> targetClass, String methodName, Class<?>[] argTypes) {
+			long hash = HashKit.FNV_OFFSET_BASIS_64;
+			
+			hash = fnv1a64(hash, targetClass.getName());
+			hash = fnv1a64(hash, methodName);
+			if (argTypes != null) {
+				for (int i=0; i<argTypes.length; i++) {
+					Class<?> type = argTypes[i];
+					if (type != null) {
+						hash = fnv1a64(hash, type.getName());
+					}
+				}
+			}
+			
+			return hash;
+		}
+		
+		private long fnv1a64(long offsetBasis, String key) {
+			long hash = offsetBasis;
+			for(int i=0, size=key.length(); i<size; i++) {
+				hash ^= key.charAt(i);
+				hash *= HashKit.FNV_PRIME_64;
+			}
+			return hash;
+		}
+	}
+}
+
+
+