Commit b5be563d authored by terrymanu's avatar terrymanu
Browse files

refactor limit

parent e40449e7

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/dialect/mysql/MySQLParser.java

+7 −7
Original line number Diff line number Diff line
@@ -27,8 +27,8 @@ import com.dangdang.ddframe.rdb.sharding.parsing.parser.context.limit.Limit; 
import com.dangdang.ddframe.rdb.sharding.parsing.parser.context.limit.LimitValue;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.exception.SQLParsingException;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.statement.SQLStatement;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.OffsetLimitToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.RowCountLimitToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.OffsetToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.RowCountToken;



/**

 * MySQL解析器.
@@ -74,7 +74,7 @@ public final class MySQLParser extends SQLParser { 
            return getLimitWithOffset(sqlStatement, parametersIndex, valueIndex, valueBeginPosition, value, isParameterForValue);

        }

        if (!isParameterForValue) {

            sqlStatement.getSqlTokens().add(new RowCountLimitToken(valueBeginPosition, value));

            sqlStatement.getSqlTokens().add(new RowCountToken(valueBeginPosition, value));

        }

        Limit result = new Limit(true);

        result.setRowCount(new LimitValue(value, valueIndex));
@@ -100,10 +100,10 @@ public final class MySQLParser extends SQLParser { 
        }

        getLexer().nextToken();

        if (!isParameterForValue) {

            sqlStatement.getSqlTokens().add(new OffsetLimitToken(valueBeginPosition, value));

            sqlStatement.getSqlTokens().add(new OffsetToken(valueBeginPosition, value));

        }

        if (!isParameterForRowCount) {

            sqlStatement.getSqlTokens().add(new RowCountLimitToken(rowCountBeginPosition, rowCount));

            sqlStatement.getSqlTokens().add(new RowCountToken(rowCountBeginPosition, rowCount));

        }

        Limit result = new Limit(true);

        result.setRowCount(new LimitValue(rowCount, rowCountIndex));
@@ -130,10 +130,10 @@ public final class MySQLParser extends SQLParser { 
        }

        getLexer().nextToken();

        if (!isParameterForOffset) {

            sqlStatement.getSqlTokens().add(new OffsetLimitToken(offsetBeginPosition, offset));

            sqlStatement.getSqlTokens().add(new OffsetToken(offsetBeginPosition, offset));

        }

        if (!isParameterForValue) {

            sqlStatement.getSqlTokens().add(new RowCountLimitToken(valueBeginPosition, value));

            sqlStatement.getSqlTokens().add(new RowCountToken(valueBeginPosition, value));

        }

        Limit result = new Limit(true);

        result.setRowCount(new LimitValue(value, valueIndex));

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/dialect/postgresql/PostgreSQLSelectParser.java

+15 −15
Original line number Diff line number Diff line
@@ -27,8 +27,8 @@ import com.dangdang.ddframe.rdb.sharding.parsing.parser.context.limit.LimitValue 
import com.dangdang.ddframe.rdb.sharding.parsing.parser.exception.SQLParsingException;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.exception.SQLParsingUnsupportedException;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.statement.select.AbstractSelectParser;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.OffsetLimitToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.RowCountLimitToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.OffsetToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.RowCountToken;

import com.google.common.base.Optional;



import static com.dangdang.ddframe.rdb.sharding.util.NumberUtil.roundHalfUp;
@@ -71,18 +71,18 @@ public class PostgreSQLSelectParser extends AbstractSelectParser { 
    }

    

    private void parseLimit() {

        Optional<LimitValue> offsetLimit = Optional.absent();

        Optional<LimitValue> rowCountLimit = Optional.absent();

        Optional<LimitValue> offset = Optional.absent();

        Optional<LimitValue> rowCount = Optional.absent();

        while (true) {

            if (getSqlParser().skipIfEqual(PostgreSQLKeyword.LIMIT)) {

                rowCountLimit = buildRowCount();

                rowCount = buildRowCount();

            } else if (getSqlParser().skipIfEqual(PostgreSQLKeyword.OFFSET)) {

                offsetLimit = buildOffsetLimit();

                offset = buildOffset();

            } else {

                break;

            }

        }

        setLimit(offsetLimit, rowCountLimit);

        setLimit(offset, rowCount);

    }

    

    private Optional<LimitValue> buildRowCount() {
@@ -96,7 +96,7 @@ public class PostgreSQLSelectParser extends AbstractSelectParser { 
            if (getSqlParser().equalAny(Literals.INT, Literals.FLOAT)) {

                rowCount = roundHalfUp(getSqlParser().getLexer().getCurrentToken().getLiterals());

                valueBeginPosition = valueBeginPosition - (rowCount + "").length();

                getSelectStatement().getSqlTokens().add(new RowCountLimitToken(valueBeginPosition, rowCount));

                getSelectStatement().getSqlTokens().add(new RowCountToken(valueBeginPosition, rowCount));

            } else if (getSqlParser().equalAny(Symbol.QUESTION)) {

                rowCountParameterIndex = parameterIndex++;

                setParametersIndex(parameterIndex);
@@ -109,7 +109,7 @@ public class PostgreSQLSelectParser extends AbstractSelectParser { 
        return Optional.of(new LimitValue(rowCount, rowCountParameterIndex));

    }

    

    private Optional<LimitValue> buildOffsetLimit() {

    private Optional<LimitValue> buildOffset() {

        int parameterIndex = getParametersIndex();

        int offset = -1;

        int offsetParameterIndex = -1;
@@ -117,7 +117,7 @@ public class PostgreSQLSelectParser extends AbstractSelectParser { 
        if (getSqlParser().equalAny(Literals.INT, Literals.FLOAT)) {

            offset = roundHalfUp(getSqlParser().getLexer().getCurrentToken().getLiterals());

            offsetBeginPosition = offsetBeginPosition - (offset + "").length();

            getSelectStatement().getSqlTokens().add(new OffsetLimitToken(offsetBeginPosition, offset));

            getSelectStatement().getSqlTokens().add(new OffsetToken(offsetBeginPosition, offset));

        } else if (getSqlParser().equalAny(Symbol.QUESTION)) {

            offsetParameterIndex = parameterIndex++;

            setParametersIndex(parameterIndex);
@@ -130,13 +130,13 @@ public class PostgreSQLSelectParser extends AbstractSelectParser { 
    }

    

    

    private void setLimit(final Optional<LimitValue> offsetLimit, final Optional<LimitValue> rowCountLimit) {

    private void setLimit(final Optional<LimitValue> offset, final Optional<LimitValue> rowCount) {

        Limit limit = new Limit(true);

        if (offsetLimit.isPresent()) {

            limit.setOffset(offsetLimit.get());

        if (offset.isPresent()) {

            limit.setOffset(offset.get());

        }

        if (rowCountLimit.isPresent()) {

            limit.setRowCount(rowCountLimit.get());

        if (rowCount.isPresent()) {

            limit.setRowCount(rowCount.get());

        }

        getSelectStatement().setLimit(limit);

    }

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/token/OffsetLimitToken.java→sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/token/OffsetToken.java

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ import lombok.RequiredArgsConstructor; 
 */

@RequiredArgsConstructor

@Getter

public final class OffsetLimitToken implements SQLToken {

public final class OffsetToken implements SQLToken {

    

    private final int beginPosition;

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/token/RowCountLimitToken.java→sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/parsing/parser/token/RowCountToken.java

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ import lombok.RequiredArgsConstructor; 
 */

@RequiredArgsConstructor

@Getter

public final class RowCountLimitToken implements SQLToken {

public final class RowCountToken implements SQLToken {

    

    private final int beginPosition;

sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/rewrite/SQLRewriteEngine.java

+12 −12
Original line number Diff line number Diff line
@@ -23,8 +23,8 @@ import com.dangdang.ddframe.rdb.sharding.api.rule.ShardingRule; 
import com.dangdang.ddframe.rdb.sharding.parsing.parser.context.limit.Limit;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.statement.SQLStatement;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.ItemsToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.OffsetLimitToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.RowCountLimitToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.OffsetToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.RowCountToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.SQLToken;

import com.dangdang.ddframe.rdb.sharding.parsing.parser.token.TableToken;

import com.dangdang.ddframe.rdb.sharding.routing.type.TableUnit;
@@ -86,10 +86,10 @@ public final class SQLRewriteEngine { 
                appendTableToken(result, (TableToken) each, count, sqlTokens);

            } else if (each instanceof ItemsToken) {

                appendItemsToken(result, (ItemsToken) each, count, sqlTokens);

            } else if (each instanceof RowCountLimitToken) {

                appendLimitRowCount(result, (RowCountLimitToken) each, count, sqlTokens, isRewriteLimit);

            } else if (each instanceof OffsetLimitToken) {

                appendLimitOffsetToken(result, (OffsetLimitToken) each, count, sqlTokens, isRewriteLimit);

            } else if (each instanceof RowCountToken) {

                appendLimitRowCount(result, (RowCountToken) each, count, sqlTokens, isRewriteLimit);

            } else if (each instanceof OffsetToken) {

                appendLimitOffsetToken(result, (OffsetToken) each, count, sqlTokens, isRewriteLimit);

            }

            count++;

        }
@@ -124,16 +124,16 @@ public final class SQLRewriteEngine { 
        sqlBuilder.appendLiterals(originalSQL.substring(beginPosition, endPosition));

    }

    

    private void appendLimitRowCount(final SQLBuilder sqlBuilder, final RowCountLimitToken rowCountLimitToken, final int count, final List<SQLToken> sqlTokens, final boolean isRewrite) {

        sqlBuilder.appendLiterals(isRewrite ? String.valueOf(rowCountLimitToken.getRowCount() + limit.getOffsetValue()) : String.valueOf(rowCountLimitToken.getRowCount()));

        int beginPosition = rowCountLimitToken.getBeginPosition() + String.valueOf(rowCountLimitToken.getRowCount()).length();

    private void appendLimitRowCount(final SQLBuilder sqlBuilder, final RowCountToken rowCountToken, final int count, final List<SQLToken> sqlTokens, final boolean isRewrite) {

        sqlBuilder.appendLiterals(isRewrite ? String.valueOf(rowCountToken.getRowCount() + limit.getOffsetValue()) : String.valueOf(rowCountToken.getRowCount()));

        int beginPosition = rowCountToken.getBeginPosition() + String.valueOf(rowCountToken.getRowCount()).length();

        int endPosition = sqlTokens.size() - 1 == count ? originalSQL.length() : sqlTokens.get(count + 1).getBeginPosition();

        sqlBuilder.appendLiterals(originalSQL.substring(beginPosition, endPosition));

    }

    

    private void appendLimitOffsetToken(final SQLBuilder sqlBuilder, final OffsetLimitToken offsetLimitToken, final int count, final List<SQLToken> sqlTokens, final boolean isRewrite) {

        sqlBuilder.appendLiterals(isRewrite ? "0" : String.valueOf(offsetLimitToken.getOffset()));

        int beginPosition = offsetLimitToken.getBeginPosition() + String.valueOf(offsetLimitToken.getOffset()).length();

    private void appendLimitOffsetToken(final SQLBuilder sqlBuilder, final OffsetToken offsetToken, final int count, final List<SQLToken> sqlTokens, final boolean isRewrite) {

        sqlBuilder.appendLiterals(isRewrite ? "0" : String.valueOf(offsetToken.getOffset()));

        int beginPosition = offsetToken.getBeginPosition() + String.valueOf(offsetToken.getOffset()).length();

        int endPosition = sqlTokens.size() - 1 == count ? originalSQL.length() : sqlTokens.get(count + 1).getBeginPosition();

        sqlBuilder.appendLiterals(originalSQL.substring(beginPosition, endPosition));

    }