### Question:
Restrictions { @Nonnull public static ColumnRestriction value() { return new ColumnRestriction("_value"); } Restrictions(); @Nonnull static Restrictions and(@Nonnull final Restrictions... restrictions); @Nonnull static Restrictions or(@Nonnull final Restrictions... restrictions); @Nonnull static ColumnRestriction measurement(); @Nonnull static ColumnRestriction field(); @Nonnull static ColumnRestriction start(); @Nonnull static ColumnRestriction stop(); @Nonnull static ColumnRestriction time(); @Nonnull static ColumnRestriction value(); @Nonnull static ColumnRestriction tag(@Nonnull final String tagName); @Nonnull static ColumnRestriction column(@Nonnull final String columnName);  }### Answer:
@Test void greaterOrEqual() { Restrictions restrictions = Restrictions.value().greaterOrEqual(10); Assertions.assertThat(restrictions.toString()).isEqualTo("r[\"_value\"] >= 10"); }
@Test void exists() { Restrictions restrictions = Restrictions.value().exists(); Assertions.assertThat(restrictions.toString()).isEqualTo("exists r[\"_value\"]"); }