本文整理汇总了Java中org.apache.drill.common.expression.SchemaPath.getRootSegment方法的典型用法代码示例。如果您正苦于以下问题：Java SchemaPath.getRootSegment方法的具体用法？Java SchemaPath.getRootSegment怎么用？Java SchemaPath.getRootSegment使用的例子？那么恭喜您, 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.drill.common.expression.SchemaPath的用法示例。
在下文中一共展示了SchemaPath.getRootSegment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: ensureAtLeastOneField
import org.apache.drill.common.expression.SchemaPath; //导入方法依赖的package包/类
@Override
public void ensureAtLeastOneField(ComplexWriter writer) {
if (!atLeastOneWrite) {
// if we had no columns, create one empty one so we can return some data for count purposes.
SchemaPath sp = columns.get(0);
PathSegment root = sp.getRootSegment();
BaseWriter.MapWriter fieldWriter = writer.rootAsMap();
while (root.getChild() != null && !root.getChild().isArray()) {
fieldWriter = fieldWriter.map(root.getNameSegment().getPath());
root = root.getChild();
}
fieldWriter.integer(root.getNameSegment().getPath());
}
}
示例2: transformColumns
import org.apache.drill.common.expression.SchemaPath; //导入方法依赖的package包/类
@Override
protected Collection<SchemaPath> transformColumns(Collection<SchemaPath> columns) {
Set<SchemaPath> transformed = Sets.newLinkedHashSet();
rowKeyOnly = true;
if (!isStarQuery()) {
for (SchemaPath column : columns) {
if (column.getRootSegment().getPath().equalsIgnoreCase(ROW_KEY)) {
transformed.add(ROW_KEY_PATH);
continue;
}
rowKeyOnly = false;
NameSegment root = column.getRootSegment();
byte[] family = root.getPath().getBytes();
transformed.add(SchemaPath.getSimplePath(root.getPath()));
PathSegment child = root.getChild();
if (child != null && child.isNamed()) {
byte[] qualifier = child.getNameSegment().getPath().getBytes();
hbaseScan.addColumn(family, qualifier);
} else {
hbaseScan.addFamily(family);
}
}
/* if only the row key was requested, add a FirstKeyOnlyFilter to the scan
* to fetch only one KV from each row. If a filter is already part of this
* scan, add the FirstKeyOnlyFilter as the LAST filter of a MUST_PASS_ALL
* FilterList.
*/
if (rowKeyOnly) {
hbaseScan.setFilter(
HBaseUtils.andFilterAtIndex(hbaseScan.getFilter(), HBaseUtils.LAST_FILTER, new FirstKeyOnlyFilter()));
}
} else {
rowKeyOnly = false;
transformed.add(ROW_KEY_PATH);
}
return transformed;
}