//$Id: Select.java 7143 2005-06-15 02:57:03Z oneovthafew $
package org.hibernate.sql;
import org.hibernate.LockMode;
import org.hibernate.dialect.Dialect;
import org.hibernate.util.StringHelper;
/**
* A simple SQL <tt>SELECT</tt> statement
* @author Gavin King
*/
public class Select {
private String selectClause;
private String fromClause;
private String outerJoinsAfterFrom;
private String whereClause;
private String outerJoinsAfterWhere;
private String orderByClause;
private String groupByClause;
private String comment;
private LockMode lockMode;
public final Dialect dialect;
private int guesstimatedBufferSize = 20;
public Select(Dialect dialect) {
this.dialect = dialect;
}
/**
* Construct an SQL <tt>SELECT</tt> statement from the given clauses
*/
public String toStatementString() {
StringBuffer buf = new StringBuffer(guesstimatedBufferSize);
if ( StringHelper.isNotEmpty(comment) ) {
buf.append("/* ").append(comment).append(" */ ");
}
buf.append("select ").append(selectClause)
.append(" from ").append(fromClause);
if ( StringHelper.isNotEmpty(outerJoinsAfterFrom) ) {
buf.append(outerJoinsAfterFrom);
}
if ( StringHelper.isNotEmpty(whereClause) || StringHelper.isNotEmpty(outerJoinsAfterWhere) ) {
buf.append(" where " );
// the outerJoinsAfterWhere needs to come before where clause to properly
// handle dynamic filters
if ( StringHelper.isNotEmpty(outerJoinsAfterWhere) ) {
buf.append(outerJoinsAfterWhere);
if ( StringHelper.isNotEmpty(whereClause) ) {
buf.append( " and " );
}
}
if ( StringHelper.isNotEmpty(whereClause) ) {
buf.append(whereClause);
}
}
if ( StringHelper.isNotEmpty(groupByClause) ) {
buf.append(" group by ").append(groupByClause);
}
if ( StringHelper.isNotEmpty(orderByClause) ) {
buf.append(" order by ").append(orderByClause);
}
if (lockMode!=null) {
buf.append( dialect.getForUpdateString(lockMode) );
}
return dialect.transformSelectString( buf.toString() );
}
/**
* Sets the fromClause.
* @param fromClause The fromClause to set
*/
public Select setFromClause(String fromClause) {
this.fromClause = fromClause;
this.guesstimatedBufferSize += fromClause.length();
return this;
}
public Select setFromClause(String tableName, String alias) {
this.fromClause = tableName + ' ' + alias;
this.guesstimatedBufferSize += fromClause.length();
return this;
}
public Select setOrderByClause(String orderByClause) {
this.orderByClause = orderByClause;
this.guesstimatedBufferSize += orderByClause.length();
return this;
}
public Select setGroupByClause(String groupByClause) {
this.groupByClause = groupByClause;
this.guesstimatedBufferSize += groupByClause.length();
return this;
}
public Select setOuterJoins(String outerJoinsAfterFrom, String outerJoinsAfterWhere) {
this.outerJoinsAfterFrom = outerJoinsAfterFrom;
// strip off any leading 'and' token
String tmpOuterJoinsAfterWhere = outerJoinsAfterWhere.trim();
if ( tmpOuterJoinsAfterWhere.startsWith("and") ) {
tmpOuterJoinsAfterWhere = tmpOuterJoinsAfterWhere.substring(4);
}
this.outerJoinsAfterWhere = tmpOuterJoinsAfterWhere;
this.guesstimatedBufferSize += outerJoinsAfterFrom.length() + outerJoinsAfterWhere.length();
return this;
}
/**
* Sets the selectClause.
* @param selectClause The selectClause to set
*/
public Select setSelectClause(String selectClause) {
this.selectClause = selectClause;
this.guesstimatedBufferSize += selectClause.length();
return this;
}
/**
* Sets the whereClause.
* @param whereClause The whereClause to set
*/
public Select setWhereClause(String whereClause) {
this.whereClause = whereClause;
this.guesstimatedBufferSize += whereClause.length();
return this;
}
public Select setComment(String comment) {
this.comment = comment;
this.guesstimatedBufferSize += comment.length();
return this;
}
public LockMode getLockMode() {
return lockMode;
}
public Select setLockMode(LockMode lockMode) {
this.lockMode = lockMode;
return this;
}
}
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