/*
* Copyright 1999-2017 Alibaba Group Holding Ltd.
*
* 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.alibaba.druid.sql.parser;
public class SQLParser {
protected final Lexer lexer;
protected String dbType;
public SQLParser(String sql, String dbType){
this(new Lexer(sql, null, dbType), dbType);
this.lexer.nextToken();
}
public SQLParser(String sql){
this(sql, null);
}
public SQLParser(Lexer lexer){
this(lexer, null);
}
public SQLParser(Lexer lexer, String dbType){
this.lexer = lexer;
this.dbType = dbType;
}
public final Lexer getLexer() {
return lexer;
}
public String getDbType() {
return dbType;
}
protected boolean identifierEquals(String text) {
return lexer.token() == Token.IDENTIFIER && lexer.stringVal().equalsIgnoreCase(text);
}
protected void acceptIdentifier(String text) {
if (identifierEquals(text)) {
lexer.nextToken();
} else {
setErrorEndPos(lexer.pos());
throw new ParserException("syntax error, expect " + text + ", actual " + lexer.token());
}
}
protected String tableAlias() {
if (lexer.token() == Token.CONNECT || lexer.token() == Token.START) {
return null;
}
if (identifierEquals("START") || identifierEquals("CONNECT")) {
return null;
}
return this.as();
}
protected String as() {
String alias = null;
final Token token = lexer.token();
if (token == Token.COMMA) {
return null;
}
if (token == Token.AS) {
lexer.nextToken();
alias = alias();
if (alias != null) {
while (lexer.token() == Token.DOT) {
lexer.nextToken();
alias += ('.' + lexer.token().name());
lexer.nextToken();
}
return alias;
}
if (lexer.token() == Token.LPAREN) {
return null;
}
throw new ParserException("Error : " + lexer.token());
}
if (lexer.token() == Token.LITERAL_ALIAS) {
alias = '"' + lexer.stringVal() + '"';
lexer.nextToken();
} else if (lexer.token() == Token.IDENTIFIER) {
alias = lexer.stringVal();
lexer.nextToken();
} else if (lexer.token() == Token.LITERAL_CHARS) {
alias = "'" + lexer.stringVal() + "'";
lexer.nextToken();
} else {
switch (lexer.token()) {
case CASE:
case USER:
case LOB:
case END:
case DEFERRED:
alias = lexer.stringVal();
lexer.nextToken();
break;
default:
break;
}
}
switch (lexer.token()) {
case KEY:
case INTERVAL:
case CONSTRAINT:
alias = lexer.token().name();
lexer.nextToken();
return alias;
default:
break;
}
return alias;
}
protected String alias() {
String alias = null;
if (lexer.token() == Token.LITERAL_ALIAS) {
alias = '"' + lexer.stringVal() + '"';
lexer.nextToken();
} else if (lexer.token() == Token.IDENTIFIER) {
alias = lexer.stringVal();
lexer.nextToken();
} else if (lexer.token() == Token.LITERAL_CHARS) {
alias = "'" + lexer.stringVal() + "'";
lexer.nextToken();
} else {
switch (lexer.token()) {
case KEY:
case INDEX:
case CASE:
case MODEL:
case PCTFREE:
case INITRANS:
case MAXTRANS:
case SEGMENT:
case CREATION:
case IMMEDIATE:
case DEFERRED:
case STORAGE:
case NEXT:
case MINEXTENTS:
case MAXEXTENTS:
case MAXSIZE:
case PCTINCREASE:
case FLASH_CACHE:
case CELL_FLASH_CACHE:
case KEEP:
case NONE:
case LOB:
case STORE:
case ROW:
case CHUNK:
case CACHE:
case NOCACHE:
case LOGGING:
case NOCOMPRESS:
case KEEP_DUPLICATES:
case EXCEPTIONS:
case PURGE:
case INITIALLY:
case END:
case COMMENT:
case ENABLE:
case DISABLE:
case SEQUENCE:
case USER:
case ANALYZE:
case OPTIMIZE:
case GRANT:
case REVOKE:
case FULL:
case TO:
case NEW:
case INTERVAL:
case LOCK:
case LIMIT:
case IDENTIFIED:
case PASSWORD:
case BINARY:
case WINDOW:
case OFFSET:
case SHARE:
case START:
case CONNECT:
case MATCHED:
case ERRORS:
case REJECT:
case UNLIMITED:
case BEGIN:
case EXCLUSIVE:
case MODE:
case ADVISE:
case TYPE:
case CLOSE:
alias = lexer.stringVal();
lexer.nextToken();
return alias;
case QUES:
alias = "?";
lexer.nextToken();
default:
break;
}
}
return alias;
}
protected void printError(Token token) {
String arround;
if (lexer.mark >= 0 && (lexer.text.length() > lexer.mark + 30)) {
if (lexer.mark - 5 > 0) {
arround = lexer.text.substring(lexer.mark - 5, lexer.mark + 30);
} else {
arround = lexer.text.substring(lexer.mark, lexer.mark + 30);
}
} else if (lexer.mark >= 0) {
if (lexer.mark - 5 > 0) {
arround = lexer.text.substring(lexer.mark - 5);
} else {
arround = lexer.text.substring(lexer.mark);
}
} else {
arround = lexer.text;
}
// throw new
// ParserException("syntax error, error arround:'"+arround+"',expect "
// + token + ", actual " + lexer.token() + " "
// + lexer.stringVal() + ", pos " + this.lexer.pos());
throw new ParserException("syntax error, error in :'" + arround + "',expect " + token + ", actual "
+ lexer.token() + " " + lexer.stringVal());
}
public void accept(Token token) {
if (lexer.token() == token) {
lexer.nextToken();
} else {
setErrorEndPos(lexer.pos());
printError(token);
}
}
public int acceptInteger() {
if (lexer.token() == Token.LITERAL_INT) {
int intVal = ((Integer) lexer.integerValue()).intValue();
lexer.nextToken();
return intVal;
} else {
throw new ParserException("syntax error, expect int, actual " + lexer.token() + " "
+ lexer.stringVal());
}
}
public void match(Token token) {
if (lexer.token() != token) {
throw new ParserException("syntax error, expect " + token + ", actual " + lexer.token() + " "
+ lexer.stringVal());
}
}
private int errorEndPos = -1;
protected void setErrorEndPos(int errPos) {
if (errPos > errorEndPos) {
errorEndPos = errPos;
}
}
}