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过滤算子
public class FiltersNodeHandler extends BaseOperatorNodeHandler {
public FiltersNodeHandler(DdlMutableGraphContext mutableGraph, DdlNode node) {
super(mutableGraph, node);
}
@Override
public PlainSelect sql() {
//获取前置节点的sql
PlainSelect preSql = prePlainSelect();
DdlNode.FilterNode filterNode = currentNode().getOperators().getFilterNode();
//最外层的条件
Boolean logic = filterNode.getLogic();
//先拼接内层的条件
List<DdlNode.Children> childrens = filterNode.getChildren();
if (!CollectionUtils.isEmpty(childrens)) {
//拼接内层条件子节点
Expression expressionOut;
for (DdlNode.Children children : childrens) {
Expression where = preSql.getWhere();
//子节点的操作字段
Boolean logicChild = children.getLogic();
//遍历第一个子节点
List<DdlNode.Operand> operands = children.getOperand();
if (CollectionUtil.isNotEmpty(operands)) {
//operand共用同一个子logicChild
//不等于1并且为奇数的时候创建
int size = operands.size();
Expression innerExpression = null;
for (int i = 0; i < size; i++) {
//为偶数才创建
if ((i & 1) == 0) {
if (Objects.nonNull(logicChild)) {
if (logicChild) {
AndExpressionExtend andExpression = new AndExpressionExtend();
if (innerExpression != null) {
andExpression.setLeftExpression(innerExpression);
}
innerExpression = andExpression;
} else {
OrExpressionExtend orExpression = new OrExpressionExtend();
if (innerExpression != null) {
orExpression.setLeftExpression(innerExpression);
}
innerExpression = orExpression;
}
}
}
String operator = operands.get(i).getOperator();
String name = operands.get(i).getName();
String value = operands.get(i).getValue();
String type = operands.get(i).getType();
Expression temp;
Expression expressionRight;
IsNullExpression isNullExpression;
InExpression inExpression;
Between between;
ExistsExpression existsExpression;
LikeExpression likeExpression;
Expression startExpression;
Expression endExpression;
String[] split;
switch (operator) {
case "=":
EqualsTo equalsTo = new EqualsTo();
equalsTo.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
equalsTo.setRightExpression(expressionRight);
temp = equalsTo;
break;
case "!=":
NotEqualsTo notEqualsTo = new NotEqualsTo();
notEqualsTo.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
notEqualsTo.setRightExpression(expressionRight);
temp = notEqualsTo;
break;
case "in":
inExpression = new InExpression();
inExpression.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
inExpression.setRightExpression(expressionRight);
temp = inExpression;
break;
case "not in":
inExpression = new InExpression();
inExpression.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
inExpression.setRightExpression(expressionRight);
inExpression.setNot(true);
temp = inExpression;
break;
case "is null":
isNullExpression = new IsNullExpression();
isNullExpression.setLeftExpression(new Column(name));
temp = isNullExpression;
break;
case "is not null":
isNullExpression = new IsNullExpression();
isNullExpression.setLeftExpression(new Column(name));
isNullExpression.setNot(true);
temp = isNullExpression;
break;
case "like":
likeExpression = new LikeExpression();
likeExpression.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
likeExpression.setRightExpression(expressionRight);
temp = likeExpression;
break;
case "not like":
likeExpression = new LikeExpression();
likeExpression.setNot(true);
likeExpression.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
likeExpression.setRightExpression(expressionRight);
temp = likeExpression;
break;
case ">":
GreaterThan greaterThan = new GreaterThan();
greaterThan.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
greaterThan.setRightExpression(expressionRight);
temp = greaterThan;
break;
case ">=":
GreaterThanEquals greaterThanEquals = new GreaterThanEquals();
greaterThanEquals.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
greaterThanEquals.setRightExpression(expressionRight);
temp = greaterThanEquals;
break;
case "<":
MinorThan minorThan = new MinorThan();
minorThan.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
minorThan.setRightExpression(expressionRight);
temp = minorThan;
break;
case "<=":
MinorThanEquals minorThanEquals = new MinorThanEquals();
minorThanEquals.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
minorThanEquals.setRightExpression(expressionRight);
temp = minorThanEquals;
break;
case "between":
between = new Between();
between.setLeftExpression(new Column(name));
split = value.split(",");
startExpression = this.getRightExpression(split[0], type);
endExpression = this.getRightExpression(split[1], type);
between.setBetweenExpressionStart(startExpression);
between.setBetweenExpressionEnd(endExpression);
temp = between;
break;
case "not between":
between = new Between();
between.setLeftExpression(new Column(name));
split = value.split(",");
startExpression = this.getRightExpression(split[0], type);
endExpression = this.getRightExpression(split[1], type);
between.setBetweenExpressionStart(startExpression);
between.setBetweenExpressionEnd(endExpression);
between.setNot(true);
temp = between;
break;
case "exists":
existsExpression = new ExistsExpression();
expressionRight = this.getRightExpression(value, type);
existsExpression.setRightExpression(expressionRight);
temp = existsExpression;
break;
case "not exists":
existsExpression = new ExistsExpression();
expressionRight = this.getRightExpression(value, type);
existsExpression.setRightExpression(expressionRight);
existsExpression.setNot(true);
temp = existsExpression;
break;
case "contains":
Matches matches = new Matches();
matches.setLeftExpression(new Column(name));
expressionRight = this.getRightExpression(value, type);
matches.setRightExpression(expressionRight);
temp = matches;
break;
default:
throw new DdlException("操作符不存在");
}
if (Objects.nonNull(logicChild)) {
if (logicChild) {
AndExpressionExtend andExpression = (AndExpressionExtend) innerExpression;
if (andExpression.getLeftExpression() == null) {
andExpression.setLeftExpression(temp);
} else {
andExpression.setRightExpression(temp);
}
innerExpression = andExpression;
} else {
OrExpressionExtend orExpression = (OrExpressionExtend) innerExpression;
if (orExpression.getLeftExpression() == null) {
orExpression.setLeftExpression(temp);
} else {
orExpression.setRightExpression(temp);
}
orExpression.setLeftExpression(temp);
innerExpression = orExpression;
}
} else {
innerExpression = temp;
}
if (i == size - 1) {
//拼接外层的条件
expressionOut = innerExpression;
if (Objects.nonNull(where)) {
if (!logic) {
expressionOut = new OrExpressionExtend(where, expressionOut);
} else {
expressionOut = new AndExpressionExtend(where, expressionOut);
}
}
preSql.setWhere(expressionOut);
}
}
}
}
}
log(preSql.toString());
return preSql;
}
/**
* 获取右端表达式
*/
private Expression getRightExpression(String value, String type) {
//默认是String类型
Expression expression = new StringValue(value);
if (DataTypeEnum.STRING.toString().equals(type)) {
expression = new StringValue(value);
}
if (DataTypeEnum.UINT_8.toString().equals(type) || DataTypeEnum.UINT32.toString().equals(type)) {
expression = new LongValue(value);
}
if (DataTypeEnum.DATE.toString().equals(type)) {
expression = new DateValue(value);
}
if (DataTypeEnum.TIME.toString().equals(type)) {
expression = new TimeValue(value);
}
if (DataTypeEnum.DOUBLE.toString().equals(type)) {
expression = new DoubleValue(value);
}
if (DataTypeEnum.HEX.toString().equals(type)) {
expression = new HexValue(value);
}
if (DataTypeEnum.NULL.toString().equals(type)) {
expression = new NullValue();
}
return expression;
}
@Override
public List<DdlColumn> columns() {
super.checkNode();
return super.preColumns();
}
}
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