com.avaje.ebean.Junction Maven / Gradle / Ivy
package com.avaje.ebean;
/**
* Represents a Conjunction or a Disjunction.
*
* Basically with a Conjunction you join together many expressions with AND, and
* with a Disjunction you join together many expressions with OR.
*
*
* Note: where() always takes you to the top level WHERE expression list.
*
*
* {@code
* Query q =
* Ebean.find(Person.class)
* .where()
* .or()
* .like("name", "Rob%")
* .eq("status", Status.NEW)
*
* // where() returns us to the top level expression list
* .where().gt("id", 10);
*
* // read as...
* // where ( ((name like Rob%) or (status = NEW)) AND (id > 10) )
* }
*
*
* Note: endJunction() takes you to the parent expression list
*
*
* {@code
* Query q =
* Ebean.find(Person.class)
* .where()
* .or()
* .like("name", "Rob%")
* .eq("status", Status.NEW)
* .endJunction()
*
* // endJunction().. takes us to the 'parent' expression list
* // which in this case is the top level (same as where())
*
* .gt("id", 10);
*
* // read as...
* // where ( ((name like Rob%) or (status = NEW)) AND (id > 10) )
* }
*
*
* Example of a nested disjunction.
*
*
* {@code
* Query q =
* Ebean.find(Customer.class)
* .where()
* .or()
* .and()
* .startsWith("name", "r")
* .eq("anniversary", onAfter)
* .endJunction()
* .and()
* .eq("status", Customer.Status.ACTIVE)
* .gt("id", 0)
* .endJunction()
* .order().asc("name");
*
* q.findList();
* String s = q.getGeneratedSql();
*
* // this produces an expression like:
* ( name like ? and c.anniversary = ? ) or (c.status = ? and c.id > ? )
*
* }
*/
public interface Junction extends Expression, ExpressionList {
/**
* The type of Junction used in full text expressions.
*/
enum Type {
/**
* AND group.
*/
AND(" and ", ""),
/**
* OR group.
*/
OR(" or ", ""),
/**
* NOT group.
*/
NOT(" and ", "not "),
/**
* Text search AND group.
*/
MUST("must", ""),
/**
* Text search NOT group.
*/
MUST_NOT("must_not", ""),
/**
* Text search OR group.
*/
SHOULD("should", "");
String prefix;
String literal;
Type(String literal, String prefix) {
this.literal = literal;
this.prefix = prefix;
}
/**
* Return the literal value for this type.
*/
public String literal() {
return literal;
}
/**
* Return the prefix value for this type.
*/
public String prefix() {
return prefix;
}
}
}