src/java.scripting/share/classes/javax/script/ScriptContext.java
changeset 47216 71c04702a3d5
parent 41554 fc6a35a87a52
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.scripting/share/classes/javax/script/ScriptContext.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,208 @@
+/*
+ * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package javax.script;
+import java.util.List;
+import java.io.Writer;
+import java.io.Reader;
+
+/**
+ * The interface whose implementing classes are used to connect Script Engines
+ * with objects, such as scoped Bindings, in hosting applications.  Each scope is a set
+ * of named attributes whose values can be set and retrieved using the
+ * <code>ScriptContext</code> methods. ScriptContexts also expose Readers and Writers
+ * that can be used by the ScriptEngines for input and output.
+ *
+ * @author Mike Grogan
+ * @since 1.6
+ */
+public interface ScriptContext {
+
+
+    /**
+     * EngineScope attributes are visible during the lifetime of a single
+     * <code>ScriptEngine</code> and a set of attributes is maintained for each
+     * engine.
+     */
+    public static final int ENGINE_SCOPE = 100;
+
+    /**
+     * GlobalScope attributes are visible to all engines created by same ScriptEngineFactory.
+     */
+    public static final int GLOBAL_SCOPE = 200;
+
+
+    /**
+     * Associates a <code>Bindings</code> instance with a particular scope in this
+     * <code>ScriptContext</code>.  Calls to the <code>getAttribute</code> and
+     * <code>setAttribute</code> methods must map to the <code>get</code> and
+     * <code>put</code> methods of the <code>Bindings</code> for the specified scope.
+     *
+     * @param  bindings The <code>Bindings</code> to associate with the given scope
+     * @param scope The scope
+     *
+     * @throws IllegalArgumentException If no <code>Bindings</code> is defined for the
+     * specified scope value in ScriptContexts of this type.
+     * @throws NullPointerException if value of scope is <code>ENGINE_SCOPE</code> and
+     * the specified <code>Bindings</code> is null.
+     *
+     */
+    public void setBindings(Bindings bindings, int scope);
+
+    /**
+     * Gets the <code>Bindings</code>  associated with the given scope in this
+     * <code>ScriptContext</code>.
+     *
+     * @return The associated <code>Bindings</code>.  Returns <code>null</code> if it has not
+     * been set.
+     *
+     * @param scope The scope
+     * @throws IllegalArgumentException If no <code>Bindings</code> is defined for the
+     * specified scope value in <code>ScriptContext</code> of this type.
+     */
+    public Bindings getBindings(int scope);
+
+    /**
+     * Sets the value of an attribute in a given scope. If the scope is <code>GLOBAL_SCOPE</code>
+     * and no Bindings is set for <code>GLOBAL_SCOPE</code>, then setAttribute call is a no-op.
+     *
+     * @param name The name of the attribute to set
+     * @param value The value of the attribute
+     * @param scope The scope in which to set the attribute
+     *
+     * @throws IllegalArgumentException
+     *         if the name is empty or if the scope is invalid.
+     * @throws NullPointerException if the name is null.
+     */
+    public void setAttribute(String name, Object value, int scope);
+
+    /**
+     * Gets the value of an attribute in a given scope.
+     *
+     * @param name The name of the attribute to retrieve.
+     * @param scope The scope in which to retrieve the attribute.
+     * @return The value of the attribute. Returns <code>null</code> is the name
+     * does not exist in the given scope.
+     *
+     * @throws IllegalArgumentException
+     *         if the name is empty or if the value of scope is invalid.
+     * @throws NullPointerException if the name is null.
+     */
+    public Object getAttribute(String name, int scope);
+
+    /**
+     * Remove an attribute in a given scope.
+     *
+     * @param name The name of the attribute to remove
+     * @param scope The scope in which to remove the attribute
+     *
+     * @return The removed value.
+     * @throws IllegalArgumentException
+     *         if the name is empty or if the scope is invalid.
+     * @throws NullPointerException if the name is null.
+     */
+    public Object removeAttribute(String name, int scope);
+
+    /**
+     * Retrieves the value of the attribute with the given name in
+     * the scope occurring earliest in the search order.  The order
+     * is determined by the numeric value of the scope parameter (lowest
+     * scope values first.)
+     *
+     * @param name The name of the attribute to retrieve.
+     * @return The value of the attribute in the lowest scope for
+     * which an attribute with the given name is defined.  Returns
+     * null if no attribute with the name exists in any scope.
+     * @throws NullPointerException if the name is null.
+     * @throws IllegalArgumentException if the name is empty.
+     */
+    public Object getAttribute(String name);
+
+
+    /**
+     * Get the lowest scope in which an attribute is defined.
+     * @param name Name of the attribute
+     * .
+     * @return The lowest scope.  Returns -1 if no attribute with the given
+     * name is defined in any scope.
+     * @throws NullPointerException if name is null.
+     * @throws IllegalArgumentException if name is empty.
+     */
+    public int getAttributesScope(String name);
+
+    /**
+     * Returns the <code>Writer</code> for scripts to use when displaying output.
+     *
+     * @return The <code>Writer</code>.
+     */
+    public Writer getWriter();
+
+
+    /**
+     * Returns the <code>Writer</code> used to display error output.
+     *
+     * @return The <code>Writer</code>
+     */
+    public Writer getErrorWriter();
+
+    /**
+     * Sets the <code>Writer</code> for scripts to use when displaying output.
+     *
+     * @param writer The new <code>Writer</code>.
+     */
+    public void setWriter(Writer writer);
+
+
+    /**
+     * Sets the <code>Writer</code> used to display error output.
+     *
+     * @param writer The <code>Writer</code>.
+     */
+    public void setErrorWriter(Writer writer);
+
+    /**
+     * Returns a <code>Reader</code> to be used by the script to read
+     * input.
+     *
+     * @return The <code>Reader</code>.
+     */
+    public Reader getReader();
+
+
+    /**
+     * Sets the <code>Reader</code> for scripts to read input
+     * .
+     * @param reader The new <code>Reader</code>.
+     */
+    public void setReader(Reader reader);
+
+    /**
+     * Returns immutable <code>List</code> of all the valid values for
+     * scope in the ScriptContext.
+     *
+     * @return list of scope values
+     */
+    public List<Integer> getScopes();
+}