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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;
import java.util.ArrayList;
import java.util.List;
import com.jfinal.template.Directive;
import com.jfinal.template.Env;
import com.jfinal.template.expr.ExprParser;
import com.jfinal.template.expr.ast.ExprList;
import com.jfinal.template.expr.ast.ForCtrl;
import com.jfinal.template.stat.ast.Break;
import com.jfinal.template.stat.ast.Call;
import com.jfinal.template.stat.ast.Continue;
import com.jfinal.template.stat.ast.Define;
import com.jfinal.template.stat.ast.Else;
import com.jfinal.template.stat.ast.ElseIf;
import com.jfinal.template.stat.ast.For;
import com.jfinal.template.stat.ast.If;
import com.jfinal.template.stat.ast.Include;
import com.jfinal.template.stat.ast.Return;
import com.jfinal.template.stat.ast.Set;
import com.jfinal.template.stat.ast.SetGlobal;
import com.jfinal.template.stat.ast.SetLocal;
import com.jfinal.template.stat.ast.Stat;
import com.jfinal.template.stat.ast.StatList;
import com.jfinal.template.stat.ast.Text;
/**
* DLRD (Double Layer Recursive Descent) Parser
*/
public class Parser {
private static final Token EOF = new Token(Symbol.EOF, -1);
private int forward = 0;
private List tokenList;
private StringBuilder content;
private String fileName;
private Env env;
public Parser(Env env, StringBuilder content, String fileName) {
this.env = env;
this.content = content;
this.fileName = fileName;
}
private Token peek() {
return tokenList.get(forward);
}
private Token move() {
return tokenList.get(++forward);
}
private Token matchPara(Token name) {
Token current = peek();
if (current.symbol == Symbol.PARA) {
move();
return current;
}
throw new ParseException("Can not match the parameter of directive #" + name.value(), getLocation(name.row));
}
private void matchEnd(Token name) {
if (peek().symbol == Symbol.END) {
move();
return ;
}
throw new ParseException("Can not match the #end of directive #" + name.value(), getLocation(name.row));
}
public StatList parse() {
tokenList = new Lexer(content, fileName).scan();
tokenList.add(EOF);
StatList statList = statList();
if (peek() != EOF) {
throw new ParseException("Syntax error: can not match " + peek().value(), getLocation(peek().row));
}
return statList;
}
private StatList statList() {
List statList = new ArrayList();
while (true) {
Stat stat = stat();
if (stat == null) {
break ;
}
if (stat instanceof Define) {
env.addFunction((Define)stat);
continue ;
}
// 过滤内容为空的 Text 节点，通常是处于两个指令之间的空白字符被移除以后的结果，详见 TextToken.deleteBlankTails()
if (stat instanceof Text && ((Text)stat).isEmpty()) {
continue ;
}
statList.add(stat);
}
return new StatList(statList);
}
private Stat stat() {
Token name = peek();
switch (name.symbol) {
case TEXT:
move();
return new Text(((TextToken)name).getContent(), env.getEngineConfig().getEncoding()).setLocation(getLocation(name.row));
case OUTPUT:
move();
Token para = matchPara(name);
Location loc = getLocation(name.row);
return env.getEngineConfig().getOutputDirective(parseExprList(para), loc).setLocation(loc);
case INCLUDE:
move();
para = matchPara(name);
return new Include(env, parseExprList(para), fileName, getLocation(name.row));
case FOR:
move();
para = matchPara(name);
StatList statList = statList();
Stat _else = null;
if (peek().symbol == Symbol.ELSE) {
move();
StatList elseStats = statList();
_else = new Else(elseStats);
}
matchEnd(name);
return new For(parseForCtrl(para), statList, _else).setLocation(getLocation(name.row));
case IF:
move();
para = matchPara(name);
statList = statList();
Stat ret = new If(parseExprList(para), statList, getLocation(name.row));
Stat current = ret;
for (Token elseIfToken = peek(); elseIfToken.symbol == Symbol.ELSEIF; elseIfToken=peek()) {
move();
para = matchPara(elseIfToken);
statList = statList();
Stat elseIf = new ElseIf(parseExprList(para), statList, getLocation(elseIfToken.row));
current.setStat(elseIf);
current = elseIf;
}
if (peek().symbol == Symbol.ELSE) {
move();
statList = statList();
_else = new Else(statList);
current.setStat(_else);
}
matchEnd(name);
return ret;
case DEFINE:
String functionName = name.value();
move();
para = matchPara(name);
statList = statList();
matchEnd(name);
return new Define(functionName, parseExprList(para), statList, getLocation(name.row));
case CALL:
functionName = name.value();
move();
para = matchPara(name);
return new Call(functionName, parseExprList(para), false).setLocation(getLocation(name.row));
case CALL_IF_DEFINED:
functionName = name.value();
move();
para = matchPara(name);
return new Call(functionName, parseExprList(para), true).setLocation(getLocation(name.row));
case SET:
move();
para = matchPara(name);
return new Set(parseExprList(para), getLocation(name.row));
case SET_LOCAL:
move();
para = matchPara(name);
return new SetLocal(parseExprList(para), getLocation(name.row));
case SET_GLOBAL:
move();
para = matchPara(name);
return new SetGlobal(parseExprList(para), getLocation(name.row));
case CONTINUE:
move();
return Continue.me;
case BREAK:
move();
return Break.me;
case RETURN:
move();
return Return.me;
case ID:
Class dire = env.getEngineConfig().getDirective(name.value());
if (dire == null) {
throw new ParseException("Directive not found: #" + name.value(), getLocation(name.row));
}
ret = createDirective(dire, name).setLocation(getLocation(name.row));
move();
para = matchPara(name);
ret.setExprList(parseExprList(para));
if (ret.hasEnd()) {
statList = statList();
ret.setStat(statList.getActualStat());
matchEnd(name);
}
return ret;
case PARA:
case ELSEIF:
case ELSE:
case END:
case EOF:
return null;
default :
throw new ParseException("Syntax error: can not match the token: " + name.value(), getLocation(name.row));
}
}
private Location getLocation(int row) {
return new Location(fileName, row);
}
private Stat createDirective(Class dire, Token name) {
try {
return dire.newInstance();
} catch (Exception e) {
throw new ParseException(e.getMessage(), getLocation(name.row), e);
}
}
private ExprList parseExprList(Token paraToken) {
return new ExprParser((ParaToken)paraToken, env.getEngineConfig(), fileName).parseExprList();
}
private ForCtrl parseForCtrl(Token paraToken) {
return new ExprParser((ParaToken)paraToken, env.getEngineConfig(), fileName).parseForCtrl();
}
}