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See:
Description
Interface Summary | |
Printer | Basic set of methods used by Session to log Status, print report or messages. |
Class Summary | |
Base | Objects of this class help to navigate through the database without execution of Zigzag expressions. |
BaseExtension | Methods extension to the Base class for advanced developers. |
ClassNavigation | This Java class contains methods for navigation inside Zigzag classes. |
Commutator | Permits to interrupt a current Script execution. |
ConsoleLineStatus | Need for setting connection of Session's LineStatuses with
the System.out standard output stream. |
ConsolePrinter | Need for setting connection of Session's Printers with
the System.out standard output stream. |
ConsoleStatus | Need for setting connection of Session's Statuses with
the System.out standard output stream. |
Error | An object that provides information if Session analysis completes with Errors. |
Failure | An object that provides information if Session execution completes with failure. |
LineStatus | A tool for logging a Session's Status namely a current Script line or a out data line. |
Name | This Name class has static methods to manipulate with strings represanting Zigzag simple objects. |
OutTable | |
PN | The PN (Processor Notation) sets the Sav Processor's notation. |
Script | Can be executed many times for different Z databases or Zigzag variables of a Session. |
Session | Is a central class executing Zigzag scripts. |
Statement | An object that represents a Zigzag statement of Script. |
Status | A tool for logging a Session's status namely a current process or Z database. |
User | Optional class for advanced developers to control access right. |
Variable | The Variable class is main instrument for interface Java with Zigzag. |
VariableExtension | Methods extension to the Variable class for advanced developers. |
Warning | An object that provides information if Session process, analysis/execution, completes with Warnings: Errors or Failures. |
WLineStatus | Prints Session's current scriptline/dataline. |
WPrinter | Prints Session's report and messages. |
WStatus | Prints Session's current process/database. |
Exception Summary | |
ZException | Provides information on exception of a Z Statement analysis or execution. |
Provides "Sav Zigzag" ORDBMS for executing Zigzag (Z) language scripts from Java(tm). Zigzag algebraic expressions reflect peculiarities of ORDBMS, for example, multi-level hierarchy, many-valued data, class inheritance and manipulation of XML data with dynamic structure. The advantage of Sav Zigzag is displayed in the high speed of the processing complexly structured hierarchy data. Expressions in Zigzag language help to select such data instantly.
The Java/Zigzag program connects with local databases via Session's
exploreBase(...) and modifyBase(...) methods. These methods may be used to create
own database server working under one JVM in multiuser regime. There are no need
for special transaction and rollback. It differs from connection through JDBC
drivers. The exploreBase
permits to read data for
the current and any other parallel threads. The modifyBase
permits
to write data by only current thread, all other are locked.
The Session
is a main class needed to execute Zigzag expressions.
Following example demonstrates a case of the data selection in the variable
$x via Session's method z(...).
Session ss = new Session(); ss.exploreBase("company"); ss.z("$x = department:(order:(date:2006-07-19))");
To navigate through the objects in a few databases simultaneously,
the Variable
and Base
objects are used. They are
very useful for any consistent data processing. Following example is based
on the example before. It illustrates iteration over the objects of $x Variable
and direct reading their "profile" attribute from the current Base.
Base base = ss.base(); Variable var = ss.var("x"); int maxlength = 0; for (String dep = var.first(); dep != null; dep = var.next()) { String profile = base.attrValue(dep, "profile"); if (profile.length() > maxlength) maxlength = profile.length(); }
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