Share project "druid" into "http://code.alibabatech.com/svn/druid"

git-svn-id: http://code.alibabatech.com/svn/druid/trunk@2 b9813039-fb51-4c41-a8b9-e21c2acb5095
2023-03-04 19:17:16 +00:00 · 2011-05-11 01:35:21 +00:00
parent 239363b62e
commit 0e60b7d988
524 changed files with 67045 additions and 0 deletions
@@ -0,0 +1,74 @@
+package com.alibaba.druid.sql.parser;
+
+public class SQLParser {
+    protected final Lexer lexer;
+
+    public SQLParser(String sql) {
+        this(new Lexer(sql));
+        this.lexer.nextToken();
+    }
+
+    public SQLParser(Lexer lexer) {
+        this.lexer = lexer;
+    }
+
+    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 SQLParseException("syntax error, expect " + text + ", actual " + lexer.token());
+        }
+    }
+
+    protected final String as() throws ParserException {
+        String rtnValue = null;
+
+        if (lexer.token() == Token.AS) {
+            lexer.nextToken();
+
+            // QS_TODO remove alias token
+            if (lexer.token() == Token.LITERAL_ALIAS) {
+                rtnValue = "'" + lexer.stringVal() + "'";
+                lexer.nextToken();
+                return rtnValue;
+            }
+
+            if (lexer.token() == Token.IDENTIFIER) {
+                rtnValue = lexer.stringVal();
+                lexer.nextToken();
+                return rtnValue;
+            }
+
+            throw new ParserException("Error", 0, 0);
+        }
+
+        if (lexer.token() == Token.LITERAL_ALIAS) {
+            rtnValue = "'" + lexer.stringVal() + "'";
+            lexer.nextToken();
+        } else if (lexer.token() == Token.IDENTIFIER) {
+            rtnValue = "'" + lexer.stringVal() + "'";
+            lexer.nextToken();
+        }
+        return rtnValue;
+    }
+
+    public void accept(Token token) {
+        if (lexer.token() == token) {
+            lexer.nextToken();
+        } else {
+            setErrorEndPos(lexer.pos());
+            throw new SQLParseException("syntax error, expect " + token + ", actual " + lexer.token());
+        }
+    }
+
+    private int errorEndPos = -1;
+
+    protected void setErrorEndPos(int errPos) {
+        if (errPos > errorEndPos) errorEndPos = errPos;
+    }
+}