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the jfinal enjoy plugin for normal java program to use sql management function.
/**
* Copyright (c) 2011-2017, James Zhan 詹波 ([email protected]).
*
* 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.stat.ast;
import com.jfinal.template.EngineConfig;
import com.jfinal.template.Env;
import com.jfinal.template.expr.ast.Assign;
import com.jfinal.template.expr.ast.Const;
import com.jfinal.template.expr.ast.Expr;
import com.jfinal.template.expr.ast.ExprList;
import com.jfinal.template.io.Writer;
import com.jfinal.template.source.ISource;
import com.jfinal.template.stat.Ctrl;
import com.jfinal.template.stat.Location;
import com.jfinal.template.stat.ParseException;
import com.jfinal.template.stat.Parser;
import com.jfinal.template.stat.Scope;
/**
* Include
*
* 1：父模板被缓存时，被 include 的模板会被间接缓存，无需关心缓存问题
* 2：同一个模板文件被多个父模板 include，所处的背景环境不同，例如各父模板中定义的模板函数不同
* 各父模板所处的相对路径不同，所以多个父模板不能共用一次 parse 出来的结果，而是在每个被include
* 的地方重新 parse
*
*
* 两种用法：
* 1：只传入一个参数，参数必须是 String 常量，如果希望第一个参数是变量可以使用 #render 指令去实现
* #include("_hot.html")
*
* 2：传入任意多个参数，除第一个参数以外的所有参数必须是赋值表达式，用于实现参数传递功能
* #include("_hot.html", title = "热门新闻", list = newsList)
*
* 上例中传递了 title、list 两个参数，可以代替父模板中的 #set 指令传参方式
* 并且此方式传入的参数只在子模板作用域有效，不会污染父模板作用域
*
* 这种传参方式有利于将子模板模块化，例如上例的调用改成如下的参数：
* #include("_hot.html", title = "热门项目", list = projectList)
* 通过这种传参方式在子模板 _hot.html 之中，完全不需要修改对于 title 与 list
* 这两个变量的处理代码，就实现了对 “热门项目” 数据的渲染
*
*/
public class Include extends Stat {
private Assign[] assignArray;
private Stat stat;
public Include(Env env, ExprList exprList, String parentFileName, Location location) {
int len = exprList.length();
if (len == 0) {
throw new ParseException("The parameter of #include directive can not be blank", location);
}
// 第一个参数必须为 String 类型
Expr expr = exprList.getExpr(0);
if (expr instanceof Const && ((Const)expr).isStr()) {
} else {
throw new ParseException("The first parameter of #include directive must be String", location);
}
// 其它参数必须为赋值表达式
if (len > 1) {
for (int i = 1; i < len; i++) {
if (!(exprList.getExpr(i) instanceof Assign)) {
throw new ParseException("The " + i + "th parameter of #include directive must be an assignment expression", location);
}
}
}
parseSubTemplate(env, ((Const)expr).getStr(), parentFileName, location);
getAssignExpression(exprList);
}
private void parseSubTemplate(Env env, String fileName, String parentFileName, Location location) {
String subFileName = getSubFileName(fileName, parentFileName);
EngineConfig config = env.getEngineConfig();
// FileSource fileSource = new FileSource(config.getBaseTemplatePath(), subFileName, config.getEncoding());
ISource fileSource = config.getSourceFactory().getSource(config.getBaseTemplatePath(), subFileName, config.getEncoding());
try {
Parser parser = new Parser(env, fileSource.getContent(), subFileName);
if (config.isDevMode()) {
env.addSource(fileSource);
}
this.stat = parser.parse().getActualStat();
} catch (Exception e) {
// 文件路径不正确抛出异常时添加 location 信息
throw new ParseException(e.getMessage(), location, e);
}
}
/**
* 获取在父模板之下子模板的最终文件名，子模板目录相对于父模板文件目录来确定
* 以 "/" 打头则以 baseTemplatePath 为根，否则以父文件所在路径为根
*/
public static String getSubFileName(String fileName, String parentFileName) {
if (parentFileName == null) {
return fileName;
}
if (fileName.startsWith("/")) {
return fileName;
}
int index = parentFileName.lastIndexOf('/');
if (index == -1) {
return fileName;
}
return parentFileName.substring(0, index + 1) + fileName;
}
private void getAssignExpression(ExprList exprList) {
int len = exprList.length();
if (len > 1) {
assignArray = new Assign[len - 1];
for (int i = 0; i < assignArray.length; i++) {
assignArray[i] = (Assign)exprList.getExpr(i + 1);
}
} else {
assignArray = null;
}
}
public void exec(Env env, Scope scope, Writer writer) {
scope = new Scope(scope);
if (assignArray != null) {
evalAssignExpression(scope);
}
stat.exec(env, scope, writer);
scope.getCtrl().setJumpNone();
}
private void evalAssignExpression(Scope scope) {
Ctrl ctrl = scope.getCtrl();
try {
ctrl.setLocalAssignment();
for (Assign assign : assignArray) {
assign.eval(scope);
}
} finally {
ctrl.setWisdomAssignment();
}
}
}