本文整理汇总了Java中org.apache.pig.Expression.Column方法的典型用法代码示例。如果您正苦于以下问题：Java Expression.Column方法的具体用法？Java Expression.Column怎么用？Java Expression.Column使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类org.apache.pig.Expression的用法示例。
在下文中一共展示了Expression.Column方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Java代码示例。
示例1: getExpression
import org.apache.pig.Expression; //导入方法依赖的package包/类
public Expression getExpression(LogicalExpression op) throws FrontendException
{
if(op instanceof ConstantExpression) {
ConstantExpression constExpr =(ConstantExpression)op ;
return new Expression.Const( constExpr.getValue() );
} else if (op instanceof ProjectExpression) {
ProjectExpression projExpr = (ProjectExpression)op;
String fieldName = projExpr.getFieldSchema().alias;
return new Expression.Column(fieldName);
} else {
if( !( op instanceof BinaryExpression ) ) {
logInternalErrorAndSetFlag();
return null;
}
BinaryExpression binOp = (BinaryExpression)op;
if(binOp instanceof AddExpression) {
return getExpression( binOp, OpType.OP_PLUS );
} else if(binOp instanceof SubtractExpression) {
return getExpression(binOp, OpType.OP_MINUS);
} else if(binOp instanceof MultiplyExpression) {
return getExpression(binOp, OpType.OP_TIMES);
} else if(binOp instanceof DivideExpression) {
return getExpression(binOp, OpType.OP_DIV);
} else if(binOp instanceof ModExpression) {
return getExpression(binOp, OpType.OP_MOD);
} else if(binOp instanceof AndExpression) {
return getExpression(binOp, OpType.OP_AND);
} else if(binOp instanceof OrExpression) {
return getExpression(binOp, OpType.OP_OR);
} else if(binOp instanceof EqualExpression) {
return getExpression(binOp, OpType.OP_EQ);
} else if(binOp instanceof NotEqualExpression) {
return getExpression(binOp, OpType.OP_NE);
} else if(binOp instanceof GreaterThanExpression) {
return getExpression(binOp, OpType.OP_GT);
} else if(binOp instanceof GreaterThanEqualExpression) {
return getExpression(binOp, OpType.OP_GE);
} else if(binOp instanceof LessThanExpression) {
return getExpression(binOp, OpType.OP_LT);
} else if(binOp instanceof LessThanEqualExpression) {
return getExpression(binOp, OpType.OP_LE);
} else if(binOp instanceof RegexExpression) {
return getExpression(binOp, OpType.OP_MATCH);
} else {
logInternalErrorAndSetFlag();
}
}
return null;
}
示例2: getExpression
import org.apache.pig.Expression; //导入方法依赖的package包/类
public Expression getExpression(LogicalExpression op) throws FrontendException
{
if(op == null) {
return null;
}
if(op instanceof ConstantExpression) {
ConstantExpression constExpr =(ConstantExpression)op ;
return new Expression.Const( constExpr.getValue() );
} else if (op instanceof ProjectExpression) {
ProjectExpression projExpr = (ProjectExpression)op;
String fieldName = projExpr.getFieldSchema().alias;
return new Expression.Column(fieldName);
} else if(op instanceof BinaryExpression) {
BinaryExpression binOp = (BinaryExpression)op;
if(binOp instanceof AddExpression) {
return getExpression( binOp, OpType.OP_PLUS );
} else if(binOp instanceof SubtractExpression) {
return getExpression(binOp, OpType.OP_MINUS);
} else if(binOp instanceof MultiplyExpression) {
return getExpression(binOp, OpType.OP_TIMES);
} else if(binOp instanceof DivideExpression) {
return getExpression(binOp, OpType.OP_DIV);
} else if(binOp instanceof ModExpression) {
return getExpression(binOp, OpType.OP_MOD);
} else if(binOp instanceof AndExpression) {
return getExpression(binOp, OpType.OP_AND);
} else if(binOp instanceof OrExpression) {
return getExpression(binOp, OpType.OP_OR);
} else if(binOp instanceof EqualExpression) {
return getExpression(binOp, OpType.OP_EQ);
} else if(binOp instanceof NotEqualExpression) {
return getExpression(binOp, OpType.OP_NE);
} else if(binOp instanceof GreaterThanExpression) {
return getExpression(binOp, OpType.OP_GT);
} else if(binOp instanceof GreaterThanEqualExpression) {
return getExpression(binOp, OpType.OP_GE);
} else if(binOp instanceof LessThanExpression) {
return getExpression(binOp, OpType.OP_LT);
} else if(binOp instanceof LessThanEqualExpression) {
return getExpression(binOp, OpType.OP_LE);
} else if(binOp instanceof RegexExpression) {
return getExpression(binOp, OpType.OP_MATCH);
} else {
LOG.error("Unsupported conversion of BinaryExpression to Expression: " + op.getName());
throw new FrontendException("Unsupported conversion of BinaryExpression to Expression: " + op.getName());
}
} else if(op instanceof UnaryExpression) {
UnaryExpression unaryOp = (UnaryExpression)op;
if(unaryOp instanceof IsNullExpression) {
return getExpression(unaryOp, OpType.OP_NULL);
} else if(unaryOp instanceof NotExpression) {
return getExpression(unaryOp, OpType.OP_NOT);
} else if(unaryOp instanceof CastExpression) {
return getExpression(unaryOp.getExpression());
} else {
LOG.error("Unsupported conversion of UnaryExpression to Expression: " + op.getName());
throw new FrontendException("Unsupported conversion of UnaryExpression to Expression: " + op.getName());
}
} else {
LOG.error("Unsupported conversion of LogicalExpression to Expression: " + op.getName());
throw new FrontendException("Unsupported conversion of LogicalExpression to Expression: " + op.getName());
}
}