Enjoy 3.2 release ^_^

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

@@ -0,0 +1,65 @@
+/**
+ * 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 java.lang.reflect.Field;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * FieldKit
+ */
+public class FieldKit {
+	
+	private static final ConcurrentHashMap<String, Object> fieldCache = new ConcurrentHashMap<String, Object>();
+	
+	public static Field getField(String key, Class<?> targetClass, String fieldName) {
+		Object field = fieldCache.get(key);
+		if (field == null) {
+			field = doGetField(targetClass, fieldName);
+			if (field != null) {
+				fieldCache.putIfAbsent(key, field);
+			} else {
+				// 对于不存在的 Field，只进行一次获取操作，主要为了支持 null safe，未来需要考虑内存泄漏风险
+				fieldCache.put(key, Boolean.FALSE);
+			}
+		}
+		return field instanceof Field ? (Field)field : null;
+	}
+	
+	private static Field doGetField(Class<?> targetClass, String fieldName) {
+		Field[] fs = targetClass.getFields();
+		for (Field f : fs) {
+			if (f.getName().equals(fieldName)) {
+				return f;
+			}
+		}
+		return null;
+	}
+	
+	/**
+	 * 获取 Field 用于缓存的 key
+	 */
+	public static String getFieldKey(Class<?> targetClass, String getterName) {
+        return new StringBuilder(64).append(targetClass.getName())
+        		.append('.').append(getterName).toString();
+    }
+}
+
+
+
+
+