语法分析器——java实现

分析器——java实现"/>

语法分析器——java实现

本人博客内编译原理文章的配套资源jar包，包括词法分析，语法分析，中间代码生成，静态语义检查，代码解释执行以及抽象语法树的手动生成：

转载请注明出处。

部分代码见——词法分析器

expr221.txt

{i1=14;i2=i1+2*3;i3=i1-5*(i2%2)+5;if(i1==i4&&i2>=20){i3=i3+1;}else{i3=i3+2;}
}

expr222.txt

{m=12;n=21;if(m<n){t=m;m=n;n=t;}r=1;d=m%n;while(r!=0){m=n;n=r;r=m%n;}
}

Lab2Main.java

package sch.cauc.edu.token;
/*** * * Lab2Main* 创建人:xrzhang * 时间：2018年5月16日-下午9:37:28 * @version 1.0.0**/
public class Lab2Main {/*** * 方法名：main* 创建人：xrzhang * 时间：2018年5月16日-下午9:37:34 * 邮件：jmzhang_15_cauc@163* @param args void* @exception * @since  1.0.0*/public static void main(String[] args) {String srcFileName="test/expr221.txt";//String srcFileName="test/expr222.txt";RecursionDescendParser parser = new RecursionDescendParser();parser.doParse(srcFileName);}
}

RecursionDescendParser.java

package sch.cauc.edu.token;import java.beans.Expression;import javax.management.timer.TimerMBean;
import javax.sound.midi.Sequence;/*** * SimpleBlock语言的递归下降分析* RecursionDescendParser* 创建人:xrzhang * 时间：2018年5月16日-上午10:14:16 * @version 1.0.0**/
public class RecursionDescendParser {private BlockLexer lexer=null;private Token lookAhead = null;public RecursionDescendParser(){}public void doParse(String filePath){lexer = new BlockLexer(filePath);this.parse();}public void matchToken(TokenType type,String functionName){System.out.println("In matchToken();-----jmzhang-----"+lookAhead.getType());if(lookAhead.getType()!=type){parsingError(type.toString(),functionName);	}lookAhead =lexer.nextToken();}public void parsingError(String types,String functionName){System.out.println("Parsing Error! in"+functionName);System.out.println("encounter "+lookAhead.getLexeme());System.out.println("at line "+lookAhead.getLine()+",column "+lookAhead.getColumn());System.out.println("while expecting "+types);System.exit(1);}/*** * 调用开始符号对应的方法，进行语法分析* 方法名：parse* 创建人：xrzhang * 时间：2018年5月16日-上午10:27:14 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/public void parse() {System.out.println("In parse();-----jmzhang-----");lookAhead=lexer.nextToken();simpleblock();System.out.println("Parsing Success!");}public void simpleblock() {System.out.println("In simpleblock();-----jmzhang-----");if(lookAhead.getType()==TokenType.LBRACKET){matchToken(TokenType.LBRACKET, "simpleblock");System.out.println("In simpleblock();-----jmzhang-----11");Sequence();System.out.println("In simpleblock();-----jmzhang-----12");matchToken(TokenType.RBRACKET, "simpleblock");System.out.println("In simpleblock();-----jmzhang-----13");if(lookAhead.getType()==TokenType.LBRACKET){simpleblock();}}else{System.out.println("In simpleblock();-----jmzhang-----2");parsingError(TokenType.LBRACKET.toString(), "simpleblock");}}/*** * sequence=assognmentStatement sequence |* 			ifStatement sequence |* 			whileStatement sequence |* 			epsilon* S->AS | IS |WS | ε* 方法名：Sequence* 创建人：xrzhang * 时间：2018年5月16日-下午8:54:23 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void Sequence() {System.out.println("In Sequence();-----jmzhang-----");if(lookAhead.getType()==TokenType.IDENTIFIER){System.out.println("In Sequence();-----jmzhang-----1");assignmentStatement();Sequence();}else if (lookAhead.getType()==TokenType.KEY_IF) {System.out.println("In Sequence();-----jmzhang-----2");ifStatement();Sequence();}else if (lookAhead.getType()==TokenType.KEY_WHILE) {System.out.println("In Sequence();-----jmzhang-----WHILE");whileStatement();Sequence();}else if (lookAhead.getType()==TokenType.RBRACKET) {//match epslonSystem.out.println("In Sequence();-----jmzhang-----3");}else {System.out.println("In Sequence();-----jmzhang-----4");String errorTypes=TokenType.IDENTIFIER.toString()+","+TokenType.RBRACKET.toString();parsingError(errorTypes, "sequence");}}/*** * 方法名：whileStatement* 创建人：xrzhang * 时间：2018年5月23日-下午7:31:56 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void whileStatement() {if (lookAhead.getType()==TokenType.KEY_WHILE){System.out.println("In whileStatement();-----jmzhang-----");matchToken(TokenType.KEY_WHILE, "whileStatement");matchToken(TokenType.LPAREN, "whileStatement");Boolexpression();matchToken(TokenType.RPAREN, "whileStatement");matchToken(TokenType.LBRACKET, "whileStatement");Sequence();matchToken(TokenType.RBRACKET, "whileStatement");}else {String errorTypes=TokenType.KEY_WHILE.toString();parsingError(errorTypes, "whileStatement");}}/*** * 方法名：Boolexpression* 创建人：xrzhang * 时间：2018年5月23日-下午7:23:48 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void Boolexpression() {System.out.println("In Boolexpression();-----jmzhang-----");if (lookAhead.getType()==TokenType.BOOL_TRUE||lookAhead.getType()==TokenType.BOOL_FALSE||lookAhead.getType()==TokenType.LPAREN||lookAhead.getType()==TokenType.IDENTIFIER||lookAhead.getType()==TokenType.INTEGER_LITERAL) {Boolterm();Boolexpression_1();}else {String errorTypes =TokenType.BOOL_TRUE.toString()+","+TokenType.BOOL_FALSE.toString()+","+TokenType.LPAREN.toString()+","+TokenType.IDENTIFIER.toString()+","+TokenType.INTEGER_LITERAL.toString();parsingError(errorTypes, "Boolexpression");}	}/*** * 方法名：Boolexpression_1* 创建人：xrzhang * 时间：2018年5月23日-下午7:22:10 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void Boolexpression_1() {System.out.println("In Boolexpression_1();-----jmzhang-----");if (lookAhead.getType()==TokenType.LOGICAL_OR) {matchToken(TokenType.LOGICAL_OR, "Boolexpression_1");Boolterm();Boolexpression_1();}else if (lookAhead.getType()==TokenType.RPAREN) {//match epslin//follow(E')={')',','}}else {String errorTypes =TokenType.LOGICAL_OR.toString()+","+TokenType.RPAREN.toString();parsingError(errorTypes, "Boolexpression_1");}	}private void Boolterm() {System.out.println("In Boolterm();-----jmzhang-----");if(lookAhead.getType()==TokenType.BOOL_TRUE||lookAhead.getType()==TokenType.BOOL_FALSE||lookAhead.getType()==TokenType.LPAREN||lookAhead.getType()==TokenType.IDENTIFIER||lookAhead.getType()==TokenType.INTEGER_LITERAL){Boolfactor();Boolterm_1();}else {String errorTypes =TokenType.BOOL_TRUE.toString()+","+TokenType.BOOL_FALSE.toString()+","+TokenType.LPAREN.toString()+","+TokenType.IDENTIFIER.toString()+","+TokenType.INTEGER_LITERAL.toString();parsingError(errorTypes, "Boolterm");}}/*** * 方法名：Boolterm_1* 创建人：xrzhang * 时间：2018年5月23日-下午7:12:13 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void Boolterm_1() {System.out.println("In Boolterm_1();-----jmzhang-----");if (lookAhead.getType()==TokenType.LOGICAL_AND) {matchToken(TokenType.LOGICAL_AND, "Boolterm_1");Boolfactor();Boolterm_1();}else if (lookAhead.getType()==TokenType.LOGICAL_OR||lookAhead.getType()==TokenType.RPAREN) {//match e[slion//follow(T')={'+','-',')',',')}else {String errorTypes =TokenType.LOGICAL_AND.toString()+","+TokenType.LOGICAL_OR.toString()+","+TokenType.RPAREN.toString()+","+TokenType.SEMICOLON.toString();parsingError(errorTypes, "Boolterm_1");}	}/*** * 方法名：Boolfactor* 创建人：xrzhang * 时间：2018年5月23日-下午7:09:50 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void Boolfactor() {System.out.println("In Boolfactor();-----jmzhang-----");if (lookAhead.getType()==TokenType.BOOL_TRUE) {matchToken(TokenType.BOOL_TRUE, "Boolfactor");}else if (lookAhead.getType()==TokenType.BOOL_FALSE) {matchToken(TokenType.BOOL_FALSE, "Boolfactor");}else if (lookAhead.getType()==TokenType.LPAREN||lookAhead.getType()==TokenType.IDENTIFIER||lookAhead.getType()==TokenType.INTEGER_LITERAL){relationlExpression();}else {String errorTypes =TokenType.BOOL_TRUE.toString()+","+TokenType.BOOL_FALSE.toString()+","+TokenType.LPAREN.toString()+","+TokenType.IDENTIFIER.toString()+","+TokenType.INTEGER_LITERAL.toString();parsingError(errorTypes, "relationlExpressionOperator");}	}/*** * 方法名：relationlExpression* 创建人：xrzhang * 时间：2018年5月23日-下午7:09:41 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void relationlExpression() {if (lookAhead.getType()==TokenType.LPAREN||lookAhead.getType()==TokenType.IDENTIFIER||lookAhead.getType()==TokenType.INTEGER_LITERAL) {System.out.println("In relationlExpression();-----jmzhang-----");expression();relationlExpressionOperator();expression();}else {String errorTypes =TokenType.LPAREN.toString()+","+TokenType.IDENTIFIER.toString()+","+TokenType.INTEGER_LITERAL.toString();parsingError(errorTypes, "relationlExpression");}}/*** * 方法名：relationlExpressionOperator* 创建人：xrzhang * 时间：2018年5月23日-下午7:09:30 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void relationlExpressionOperator() {System.out.println("In relationlExpressionOperator();-----jmzhang-----");if (lookAhead.getType()==TokenType.LESS) {matchToken(TokenType.LESS, "relationlExpressionOperator");}else if (lookAhead.getType()==TokenType.GREATER) {matchToken(TokenType.GREATER, "relationlExpressionOperator");}else if (lookAhead.getType()==TokenType.LESS_EQUAL) {matchToken(TokenType.LESS_EQUAL, "relationlExpressionOperator");}else if (lookAhead.getType()==TokenType.GREATER_EQUAL) {matchToken(TokenType.GREATER_EQUAL, "relationlExpressionOperator");}else if (lookAhead.getType()==TokenType.NOT_EQUAL) {matchToken(TokenType.NOT_EQUAL, "relationlExpressionOperator");}else if(lookAhead.getType()==TokenType.EQUAL) {matchToken(TokenType.EQUAL, "relationlExpressionOperator");}else {String errorTypes =TokenType.LESS.toString()+","+TokenType.GREATER.toString()+","+TokenType.LESS_EQUAL.toString()+","+TokenType.GREATER_EQUAL.toString()+","+TokenType.NOT_EQUAL.toString()+","+TokenType.EQUAL.toString();parsingError(errorTypes, "relationlExpressionOperator");}}/*** * 方法名：ifStatement* 创建人：xrzhang * 时间：2018年5月23日-下午7:29:16 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void ifStatement() {System.out.println("In ifStatement();-----jmzhang-----");if(lookAhead.getType()==TokenType.KEY_IF){matchToken(TokenType.KEY_IF, "ifStatement");matchToken(TokenType.LPAREN, "ifStatement");Boolexpression();matchToken(TokenType.RPAREN, "ifStatement");matchToken(TokenType.LBRACKET, "ifStatement");Sequence();matchToken(TokenType.RBRACKET, "ifStatement");if(lookAhead.getType()==TokenType.KEY_ELSE){OptionalElse();}}else {System.out.println("In OptionalElse();-----jmzhang-----3");String errorTypes =TokenType.KEY_IF.toString();parsingError(errorTypes, "ifStatement");}}/*** 方法名：OptionalElse* 创建人：xrzhang * 时间：2018年5月23日-下午7:27:53 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void OptionalElse() {System.out.println("In OptionalElse();-----jmzhang-----");if(lookAhead.getType()==TokenType.KEY_ELSE){System.out.println("In OptionalElse();-----jmzhang-----1");matchToken(TokenType.KEY_ELSE, "OptionalElse");matchToken(TokenType.LBRACKET, "OptionalElse");Sequence();matchToken(TokenType.RBRACKET, "OptionalElse");}else if (lookAhead.getType()==TokenType.RBRACKET||lookAhead.getType()==TokenType.KEY_IF||lookAhead.getType()==TokenType.KEY_WHILE||lookAhead.getType()==TokenType.IDENTIFIER) {//match epslionSystem.out.println("In OptionalElse();-----jmzhang-----2");}else {System.out.println("In OptionalElse();-----jmzhang-----3");String errorTypes =TokenType.KEY_ELSE.toString()+","+TokenType.RBRACKET.toString()+","+TokenType.KEY_IF.toString()+","+TokenType.KEY_WHILE.toString()+","+TokenType.IDENTIFIER.toString();parsingError(errorTypes, "OptionalElse");}}/*** * assignmentStatement =IDENTIFIER ASSIGN expression SEMICOLON* A->id = E;* 方法名：assignmentStatement* 创建人：xrzhang * 时间：2018年5月16日-下午8:56:26 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void assignmentStatement() {System.out.println("In assignmentStatement();-----jmzhang-----");if (lookAhead.getType()==TokenType.IDENTIFIER) {matchToken(TokenType.IDENTIFIER, "assignmentStatement");matchToken(TokenType.ASSIGN, "assignmentStatement");expression();matchToken(TokenType.SEMICOLON, "assignmentStatement");}else {String errorTypes=TokenType.IDENTIFIER.toString();parsingError(errorTypes, "assignmentStatement");}}/*** * expression = term expression_1* E->TE'* 方法名：expression* 创建人：xrzhang * 时间：2018年5月16日-下午9:00:40 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void expression() {System.out.println("In expression();-----jmzhang-----");if (lookAhead.getType()==TokenType.IDENTIFIER||lookAhead.getType()==TokenType.LPAREN||lookAhead.getType()==TokenType.INTEGER_LITERAL) {term();expression_1();}else {String errorTypes =TokenType.IDENTIFIER.toString()+","+TokenType.INTEGER_LITERAL.toString()+","+TokenType.LPAREN.toString();parsingError(errorTypes, "expression");}}/*** * expression_1=PLUS term expression_1 | MINUS term expression_1 | epslin* E'->TE' | -TE' | ε* 方法名：expression_1* 创建人：xrzhang * 时间：2018年5月16日-下午9:06:26 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void expression_1() {System.out.println("In expression_1();-----jmzhang-----");if (lookAhead.getType()==TokenType.PLUS) {System.out.println("In expression_1();-----jmzhang-----1");matchToken(TokenType.PLUS, "expression_1");term();expression_1();}else if (lookAhead.getType()==TokenType.MINUS) {System.out.println("In expression_1();-----jmzhang-----2");matchToken(TokenType.MINUS, "expression_1");term();expression_1();}else if (lookAhead.getType()==TokenType.SEMICOLON||lookAhead.getType()==TokenType.LESS||lookAhead.getType()==TokenType.GREATER||lookAhead.getType()==TokenType.LESS_EQUAL||lookAhead.getType()==TokenType.GREATER_EQUAL||lookAhead.getType()==TokenType.NOT_EQUAL||lookAhead.getType()==TokenType.EQUAL||lookAhead.getType()==TokenType.LOGICAL_AND||lookAhead.getType()==TokenType.LOGICAL_OR||lookAhead.getType()==TokenType.RPAREN) {System.out.println("In expression_1();-----jmzhang-----3");//match epslin//follow(E')={')',','}}else {System.out.println("In expression_1();-----jmzhang-----4");String errorTypes =TokenType.PLUS.toString()+","+TokenType.MINUS.toString()+","+TokenType.SEMICOLON.toString()+","+TokenType.LESS.toString()+","+TokenType.GREATER.toString()+","+TokenType.LESS_EQUAL.toString()+","+TokenType.GREATER_EQUAL.toString()+","+TokenType.NOT_EQUAL.toString()+","+TokenType.EQUAL.toString();parsingError(errorTypes, "expression_1");}}/*** * term=factor term_1* T->FT'* 方法名：term* 创建人：xrzhang * 时间：2018年5月16日-下午9:16:51 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void term() {System.out.println("In term();-----jmzhang-----");if(lookAhead.getType()==TokenType.IDENTIFIER||lookAhead.getType()==TokenType.LPAREN||lookAhead.getType()==TokenType.INTEGER_LITERAL){factor();term_1();}else {String errorTypes =TokenType.IDENTIFIER.toString()+","+TokenType.INTEGER_LITERAL.toString()+","+TokenType.LPAREN.toString();parsingError(errorTypes, "term");}}/*** * term_1=MULT factor term_1 | DIV factor term_1 | MOD factor term_1 | epslin* T'->*FT' | /FT' |%FT'|ε* 方法名：term_1* 创建人：xrzhang * 时间：2018年5月16日-下午9:20:00 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void term_1() {System.out.println("In term_1();-----jmzhang-----");if (lookAhead.getType()==TokenType.TIMES) {matchToken(TokenType.TIMES, "term_1");factor();term_1();}else if (lookAhead.getType()==TokenType.DIVIDE) {matchToken(TokenType.DIVIDE, "term_1");factor();term_1();}else if (lookAhead.getType()==TokenType.REMAINDER) {matchToken(TokenType.REMAINDER, "term_1");factor();term_1();}else if (lookAhead.getType()==TokenType.PLUS||lookAhead.getType()==TokenType.MINUS||lookAhead.getType()==TokenType.SEMICOLON||lookAhead.getType()==TokenType.LESS||lookAhead.getType()==TokenType.GREATER||lookAhead.getType()==TokenType.LESS_EQUAL||lookAhead.getType()==TokenType.GREATER_EQUAL||lookAhead.getType()==TokenType.NOT_EQUAL||lookAhead.getType()==TokenType.EQUAL||lookAhead.getType()==TokenType.LOGICAL_AND||lookAhead.getType()==TokenType.LOGICAL_OR||lookAhead.getType()==TokenType.RPAREN) {//match e[slion//follow(T')={'+','-',')',',')}else {String errorTypes =TokenType.TIMES.toString()+","+TokenType.DIVIDE.toString()+","+TokenType.REMAINDER.toString()+","+TokenType.PLUS.toString()+","+TokenType.MINUS.toString()+","+TokenType.SEMICOLON.toString()+","+TokenType.LESS.toString()+","+TokenType.GREATER.toString()+","+TokenType.LESS_EQUAL.toString()+","+TokenType.GREATER_EQUAL.toString()+","+TokenType.NOT_EQUAL.toString()+","+TokenType.EQUAL.toString()+","+TokenType.LOGICAL_AND.toString()+","+TokenType.LOGICAL_OR.toString();System.out.println("lookAhead.getType()"+lookAhead.getType());parsingError(errorTypes, "term_1");}}/*** * factor = LPAREN expression RPAREN | IDENTIFER|INTEGER_LITERAL* F->(E)|id| number* 方法名：factor* 创建人：xrzhang * 时间：2018年5月16日-下午9:29:47 * 邮件：jmzhang_15_cauc@163 void* @exception * @since  1.0.0*/private void factor() {System.out.println("In factor();-----jmzhang-----");if (lookAhead.getType()==TokenType.LPAREN) {matchToken(TokenType.LPAREN, "factor");expression();matchToken(TokenType.RPAREN, "factor");}else if (lookAhead.getType()==TokenType.IDENTIFIER) {matchToken(TokenType.IDENTIFIER, "factor");}else if (lookAhead.getType()==TokenType.INTEGER_LITERAL) {matchToken(TokenType.INTEGER_LITERAL, "factor");}else {String errorTypes =TokenType.LPAREN.toString()+","+TokenType.IDENTIFIER.toString()+","+TokenType.INTEGER_LITERAL.toString();parsingError(errorTypes, "factor");}}
}