/*
* JEF - Copyright 2009-2010 Jiyi (mr.jiyi@gmail.com)
*
* 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 jef.database.query;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import jef.common.PairSO;
import jef.common.log.LogUtil;
import jef.database.DbUtils;
import jef.database.Field;
import jef.database.QueryAlias;
import jef.database.dialect.DatabaseDialect;
import jef.database.jsqlparser.JPQLSelectConvert;
import jef.database.jsqlparser.SqlFunctionlocalization;
import jef.database.jsqlparser.UndoableVisitor;
import jef.database.jsqlparser.expression.Column;
import jef.database.jsqlparser.expression.JpqlParameter;
import jef.database.jsqlparser.parser.ParseException;
import jef.database.jsqlparser.visitor.Expression;
import jef.database.jsqlparser.visitor.ExpressionType;
import jef.database.jsqlparser.visitor.ExpressionVisitor;
import jef.database.jsqlparser.visitor.VisitorAdapter;
import jef.database.meta.ITableMetadata;
import jef.database.meta.MetaHolder;
import jef.database.wrapper.variable.ConstantVariable;
import jef.database.wrapper.variable.Variable;
import com.google.common.base.Objects;
public class JpqlExpression implements Expression, LazyQueryBindField {
protected Query<?> instance;
protected boolean bindBase;
protected Expression st;
// 当基于某个对象进行带函数的查询时，使用此方法构造
// 但是目前JEF上不支持SQL词法分析
public JpqlExpression(String str, Query<?> clz) {
try {
this.st = DbUtils.parseExpression(str);
} catch (ParseException e) {
LogUtil.exception(e);
throw new RuntimeException(e.getMessage());
}
this.instance = clz;
}
public JpqlExpression(Expression exp, Query<?> q) {
this.st = exp;
this.instance = q;
}
public JpqlExpression(String str) {
this(str, (Query<?>) null);
}
/*
* 1 #toSqlAndBindAttribs 不支持使用绑定变量，采用新的函数，逐渐代替旧的函数 2
* 最终替代旧的#toSqlAndBindAttrib方法
*/
public PairSO<List<Variable>> toSqlAndBindAttribs2(final SqlContext context, final DatabaseDialect profile) {
// 本地化
st.accept(new SqlFunctionlocalization(profile, null));
// 属性提供
final List<Variable> binder =new ArrayList<Variable>();
if (context != null) {
@SuppressWarnings("unchecked")
final Map<String, Object> attribs = context.attribute == null ? Collections.EMPTY_MAP : context.attribute;
st.accept(new VisitorAdapter() {
@Override
public void visit(JpqlParameter parameter) {
if (parameter.getName() == null)
return;
Object obj = attribs.get(parameter.getName());
if (obj == null) {
if (!attribs.containsKey(parameter.getName())) {
throw new IllegalArgumentException("You have not set the value of param '" + parameter.getName() + "'");
} else {
parameter.setResolved("null");
}
} else {
parameter.setResolved(1);
binder.add(new ConstantVariable(obj));
//原地解析(没有使用绑定变量)
// if (obj instanceof Number) {
// parameter.setResolved(String.valueOf(obj));
// } else {
// parameter.setResolved("'" + String.valueOf(obj) + "'");
// }
}
}
});
}
// 字段转换
String result;
if (instance == null) {
st.accept(new JPQLSelectConvert(profile));
result = st.toString();
} else {
String alias;
if (context == null) {
// TODO 从目前来看 context==null的情况应该几乎没有了
alias = null;
} else if (bindBase && context.queries.get(0).getQuery().getMeta() == instance.getMeta()) {
alias = context.queries.get(0).getAlias();
} else {
alias = context.getAliasOf(instance);
}
ColumnAliasApplier convert = new ColumnAliasApplier(alias, profile);
st.accept(convert);
result = st.toString();
convert.undo();
}
return new PairSO<List<Variable>>(result, binder);
}
/**
*
* @param context
* @param profile
* @deprecated 后续要重构为使用toSqlAndBindAttribs2方法
* @return
*/
public String toSqlAndBindAttribs(final SqlContext context, final DatabaseDialect profile) {
// 本地化
st.accept(new SqlFunctionlocalization(profile, null));
// 属性提供
if (context != null) {
@SuppressWarnings("unchecked")
final Map<String, Object> attribs = context.attribute == null ? Collections.EMPTY_MAP : context.attribute;
st.accept(new VisitorAdapter() {
@Override
public void visit(JpqlParameter parameter) {
if (parameter.getName() == null)
return;
Object obj = attribs.get(parameter.getName());
if (obj == null) {
if (!attribs.containsKey(parameter.getName())) {
throw new IllegalArgumentException("You have not set the value of param '" + parameter.getName() + "'");
} else {
parameter.setResolved("null");
}
} else {
if (obj instanceof Number) {
parameter.setResolved(String.valueOf(obj));
} else {
parameter.setResolved("'" + String.valueOf(obj) + "'");
}
}
}
});
}
// 字段转换
String result;
if (instance == null) {
st.accept(new JPQLSelectConvert(profile));
result = st.toString();
} else {
String alias;
if (context == null) {
// TODO 从目前来看 context==null的情况应该几乎没有了
alias = null;
} else if (bindBase && context.queries.get(0).getQuery().getMeta() == instance.getMeta()) {
alias = context.queries.get(0).getAlias();
} else {
alias = context.getAliasOf(instance);
}
ColumnAliasApplier convert = new ColumnAliasApplier(alias, profile);
st.accept(convert);
result = st.toString();
convert.undo();
}
return result;
}
/**
* 用于对简单对象中的列前引用的表别名进行替换的程序
*
* @author Administrator
*
*/
private class ColumnAliasApplier extends UndoableVisitor<Column, String[]> {
private String alias;
private DatabaseDialect profile;
public ColumnAliasApplier(String alias, DatabaseDialect profile) {
this.alias = alias;
this.profile = profile;
}
@Override
public void visit(Column tableColumn) {
if (instance == null) {
return;
}
ITableMetadata meta = MetaHolder.getMeta(instance.getInstance());
Field f = meta.getField(tableColumn.getColumnName());
String oldAlias = tableColumn.getTableAlias();
if (f != null) {
savePoint(tableColumn, new String[] { oldAlias, tableColumn.getColumnName() });
tableColumn.setTableAlias(alias);
tableColumn.setColumnName(meta.getColumnName(f, profile, true));
} else {
// FIXME 现在设计没找到列是不替换名称的
}
}
@Override
protected void undo(Column key, String[] value) {
key.setTableAlias(value[0]);
key.setColumnName(value[1]);
}
}
public boolean isBind() {
return instance != null;
}
public ITableMetadata getMeta() {
if (instance == null)
return null;
return MetaHolder.getMeta(instance.getInstance());
}
public String toString() {
return st.toString();
}
public void appendTo(StringBuilder sb) {
st.appendTo(sb);
}
public Query<?> getInstanceQuery(AbstractEntityMappingProvider context) {
if (instance != null) {
return instance;
}
if (context != null && context.getReference().size() == 1) {
this.instance = ((QueryAlias) context.queries.get(0)).getQuery();
}
return instance;
}
public void accept(ExpressionVisitor expressionVisitor) {
throw new UnsupportedOperationException();
}
@Override
public int hashCode() {
return st.hashCode();
}
@Override
public boolean equals(Object obj) {
if (obj == null || !JpqlExpression.class.isAssignableFrom(obj.getClass()))
return false;
JpqlExpression o = (JpqlExpression) obj;
if (!Objects.equal(this.instance, o.instance))
return false;
if (!Objects.equal(this.st, o.st))
return false;
return true;
}
public JpqlExpression bind(Query<?> query) {
this.instance = query;
return this;
}
public void setBind(Query<?> query) {
this.instance = query;
}
public ExpressionType getType() {
return ExpressionType.complex;
}
public boolean isBindBase() {
return bindBase;
}
public void setBindBase(boolean bindBase) {
this.bindBase = bindBase;
}
}