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7.3.2 Database of Persistent Objects

Since transparency was a major concern throughout the design of the entire environment, the persistent storage of objects is performed in a way that can easily be understood. Figure 7.2 depicts the tree which results from the registration of various objects with the Persistent Storage Manager. Each branch of Figure 7.2 corresponds to a file in a directory (which is by default ~/.siesta/) holding the subtree. Example 7.2 depicts the file ~/.siesta/system containing the subtree of branch system of Figure 7.2. This branch contains six objects available under the names In order to be able to distinguish objects, which are located on leaves of the tree, from branches of the tree, the latter are surrounded by double quotes in contrast to class names which are not marked this way (see Example 7.2).

% latex2html id marker 7114\centering
...tent objects managed
by the \textsl{Persistent Storage Manager}{}.}

% latex2html id marker 7119\scriptsize
...e of objects
registered with names starting with \texttt{system}.}

Rudi Strasser