Author: pier
Date: Sun Oct 31 19:12:48 2004
New Revision: 56188
Added:
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Abstract.java
Modified:
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Block.java
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Descriptor.java
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/runtime/Instance.java
Log:
Separating extendibilty and provisions to achieve full multiple inheritance of
blocks
Added:
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Abstract.java
==============================================================================
--- (empty file)
+++
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Abstract.java
Sun Oct 31 19:12:48 2004
@@ -0,0 +1,77 @@
+/*
===============================================================================
*
+ * Copyright (C) 1999-2004, The Apache Software Foundation. All rights
reserved. *
+ *
*
+ * Licensed under the Apache License, Version 2.0 (the "License"). You may not
use *
+ * this file except in compliance with the License. You may obtain a copy of
the *
+ * License at <http://www.apache.org/licenses/LICENSE-2.0>.
*
+ *
*
+ * Unless required by applicable law or agreed to in writing, software
distributed *
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT
WARRANTIES OR *
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for
the *
+ * specific language governing permissions and limitations under the License.
*
+ *
===============================================================================
*/
+package org.apache.cocoon.kernel.description;
+
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Set;
+
+import org.apache.cocoon.kernel.KernelException;
+import org.apache.cocoon.kernel.configuration.Configuration;
+
+/**
+ * <p>An [EMAIL PROTECTED] Abstract} represents a an descriptor, or a block
providing only
+ * libraries, but no usable components.</p>
+ *
+ * @author <a href="mailto:[EMAIL PROTECTED]">Pier Fumagalli</a>
+ * @author Copyright © 2000-2004 <a href="http://www.apache.org/";>The
Apache
+ * Software Foundation</a>. All rights reserved.
+ */
+public class Abstract extends Descriptor {
+
+ /** <p>The array of identifiers of all extended blocks.</p> */
+ private String[] extensions = null;
+
+ /**
+ * <p>Create a new [EMAIL PROTECTED] Abstract} instance.</p>
+ */
+ public Abstract(Configuration configuration)
+ throws KernelException {
+ super(configuration);
+
+ /* Specific block stuff */
+ String name = configuration.name();
+ if ((!"block".equals(name)) && (!"abstract".equals(name))) {
+ throw new KernelException("Invalid root element name for abstract "
+ + " descriptor at " + configuration.location());
+ }
+
+ /* Extensions */
+ Iterator iterator = configuration.children(NAMESPACE, "extends");
+ Set list = new HashSet();
+ while (iterator.hasNext()) {
+ Configuration current = (Configuration) iterator.next();
+ String id = current.getStringAttribute("block", null);
+ if (id == null) {
+ throw new KernelException("Extended block identifier not speci"
+ + "fied in descriptor at " + configuration.location());
+ }
+ list.add(id);
+ }
+ this.extensions = (String[]) list.toArray(new String[list.size()]);
+ }
+
+ /**
+ * <p>Return the type of this descriptor.</p>
+ */
+ public int getType() {
+ return Descriptor.ABSTRACT;
+ }
+
+ /**
+ * <p>Return an array of all extended block identifers.</p>
+ */
+ public String[] getExtendedBlocks() {
+ return(this.extensions);
+ }
+}
Modified:
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Block.java
==============================================================================
---
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Block.java
(original)
+++
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Block.java
Sun Oct 31 19:12:48 2004
@@ -20,13 +20,13 @@
import org.apache.cocoon.kernel.configuration.Configuration;
/**
- * <p>An [EMAIL PROTECTED] Block} represents an block descriptor.</p>
+ * <p>A [EMAIL PROTECTED] Block} represents a block descriptor.</p>
*
* @author <a href="mailto:[EMAIL PROTECTED]">Pier Fumagalli</a>
* @author Copyright © 2000-2004 <a href="http://www.apache.org/";>The
Apache
* Software Foundation</a>. All rights reserved.
*/
-public class Block extends Descriptor {
+public class Block extends Abstract {
/** <p>The name of the exposed Java interface.</p> */
private String clazz = null;
@@ -36,8 +36,6 @@
private String destroyer = null;
/** <p>Whether the component is a singleton or not.</p> */
private boolean singleton = true;
- /** <p>The array of identifiers of all extended blocks.</p> */
- private String[] extensions = null;
/** <p>The array of identifiers of all implemented interfaces.</p> */
private String[] implementations = null;
@@ -52,19 +50,34 @@
/* Parse all generic stuff */
super(configuration);
- /* Specific interface stuff */
+ /* Specific block stuff */
if (! "block".equals(configuration.name())) {
- throw new KernelException("Invalid root element name for interface
"
+ throw new KernelException("Invalid root element name for block "
+ " descriptor at " + configuration.location());
}
+ /* Implementations */
+ Iterator iterator = configuration.children(NAMESPACE, "extends");
+ Set list = new HashSet();
+ while (iterator.hasNext()) {
+ Configuration current = (Configuration) iterator.next();
+ String id = current.getStringAttribute("block", null);
+ if (id == null) {
+ throw new KernelException("Extended block identifier not speci"
+ + "fied in descriptor at " + configuration.location());
+ }
+ list.add(id);
+ }
+ this.implementations = (String[]) list.toArray(new
String[list.size()]);
+
/* Provision */
Configuration provides = configuration.child(NAMESPACE, "provides");
this.clazz = provides.getStringAttribute("component", null);
- if (this.clazz == null) {
- throw new KernelException("Provided class name not specified at "
- + provides.location());
- }
+
+ /* No class? Abstract block, only libraries */
+ if (this.clazz == null) return;
+
+ /* Process initializer, destroyer, and singleton */
this.initializer = provides.getStringAttribute("initialize", null);
this.destroyer = provides.getStringAttribute("destroy", null);
this.singleton = provides.getBooleanAttribute("singleton", true);
@@ -73,37 +86,13 @@
+ "or destroyer method at " + provides.location());
}
- /* Extensions and implementations */
- Iterator iterator = null;
- Set list = null;
-
- /* Extensions */
- iterator = configuration.children(NAMESPACE, "extends");
- list = new HashSet();
- while (iterator.hasNext()) {
- Configuration current = (Configuration) iterator.next();
- String id = current.getStringAttribute("block", null);
- if (id == null) {
- throw new KernelException("Extended block identifier not speci"
- + "fied in descriptor at " + configuration.location());
- }
- list.add(id);
- }
- this.extensions = (String[]) list.toArray(new String[list.size()]);
+ }
- /* Implementations */
- iterator = configuration.children(NAMESPACE, "extends");
- list = new HashSet();
- while (iterator.hasNext()) {
- Configuration current = (Configuration) iterator.next();
- String id = current.getStringAttribute("block", null);
- if (id == null) {
- throw new KernelException("Extended block identifier not speci"
- + "fied in descriptor at " + configuration.location());
- }
- list.add(id);
- }
- this.implementations = (String[]) list.toArray(new
String[list.size()]);
+ /**
+ * <p>Check if this block is an <i>abstract</i> block.</p>
+ */
+ public boolean isAbstract() {
+ return(this.clazz == null);
}
/**
@@ -132,13 +121,6 @@
*/
public boolean isSingletonComponent() {
return(this.singleton);
- }
-
- /**
- * <p>Return an array of all extended block identifers.</p>
- */
- public String[] getExtendedBlocks() {
- return(this.extensions);
}
/**
Modified:
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Descriptor.java
==============================================================================
---
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Descriptor.java
(original)
+++
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/description/Descriptor.java
Sun Oct 31 19:12:48 2004
@@ -33,6 +33,8 @@
/** <p>The namespace declaration of the XML descriptor.</p> */
public static final String NAMESPACE =
"http://apache.org/cocoon/blocks/descriptor/1.0";;
+ /** <p>The type identifying an abstract descriptor.</p> */
+ public static final int ABSTRACT = 0;
/** <p>The type identifying a block descriptor.</p> */
public static final int BLOCK = 1;
/** <p>The type identifying an interface descriptor.</p> */
Modified:
cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/runtime/Instance.java
==============================================================================
--- cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/runtime/Instance.java
(original)
+++ cocoon/whiteboard/kernel/src/org/apache/cocoon/kernel/runtime/Instance.java
Sun Oct 31 19:12:48 2004
@@ -19,6 +19,7 @@
import java.util.Set;
import org.apache.cocoon.kernel.KernelException;
+import org.apache.cocoon.kernel.description.Abstract;
import org.apache.cocoon.kernel.description.Block;
import org.apache.cocoon.kernel.description.Descriptor;
import org.apache.cocoon.kernel.description.Interface;
@@ -61,7 +62,7 @@
throw new KernelException("Block " + block.toString()
+ " implements unknown block " + implementations[k]);
}
- if (descriptor.getType() != Descriptor.BLOCK) {
+ if (descriptor.getType() != Descriptor.INTERFACE) {
throw new KernelException("Block " + block.toString()
+ " implements non-interface " +
descriptor.toString());
}
@@ -85,12 +86,12 @@
throw new KernelException("Block " + block.toString()
+ " extends unknown block " + extensions[k]);
}
- if (descriptor.getType() != Descriptor.BLOCK) {
+ if (descriptor.getType() == Descriptor.INTERFACE) {
throw new KernelException("Block " + block.toString()
- + " extends non-block " + descriptor.toString());
+ + " extends interface " + descriptor.toString());
}
collector.add(block);
- this.process(library, (Block) descriptor, collector, interfaces);
+ this.process(library, (Abstract) descriptor, collector,
interfaces);
}
/* Resolve the component class and verify that it implements what it
must */
@@ -167,51 +168,53 @@
/**
* <p>Add all libraries provided by a given block and its super-blocks.</p>
*/
- private void process(Library library, Block block, Set collector, Set
interfaces)
+ private void process(Library lib, Abstract abs, Set collector, Set
interfaces)
throws KernelException {
/* Check circularities */
- if (collector.contains(block)) {
+ if (collector.contains(abs)) {
throw new KernelException("Circularity exception analysing "
- + "extensions for block " + block.toString());
+ + "extensions for block " + abs.toString());
}
- collector.add(block);
+ collector.add(abs);
/* Process interfaces */
- String implementations[] = block.getImplementedInterfaces();
- for (int k = 0; k < implementations.length; k++) {
- Descriptor descriptor = library.get(implementations[k]);
- if (descriptor == null) {
- throw new KernelException("Block " + block.toString()
- + " implements unknown block " + implementations[k]);
- }
- if (descriptor.getType() != Descriptor.BLOCK) {
- throw new KernelException("Block " + block.toString()
- + " implements non-interface " +
descriptor.toString());
- }
-
- String clazz = ((Interface) descriptor).getInterface();
- try {
- interfaces.add(this.getParent().loadClass(clazz));
- } catch (ClassNotFoundException e) {
- throw new KernelException("Cant find class " + clazz + "
exposed by "
- + "interface " + descriptor.toString() + " implemented
by "
- + block.toString());
+ if (abs.getType() == Descriptor.BLOCK) {
+ String implementations[] = ((Block)abs).getImplementedInterfaces();
+ for (int k = 0; k < implementations.length; k++) {
+ Descriptor descriptor = lib.get(implementations[k]);
+ if (descriptor == null) {
+ throw new KernelException("Block " + abs.toString() + "
imple"
+ + "ments unknown interface " + implementations[k]);
+ }
+ if (descriptor.getType() != Descriptor.INTERFACE) {
+ throw new KernelException("Block " + abs.toString()
+ + " implements non-interface " +
descriptor.toString());
+ }
+
+ String clazz = ((Interface) descriptor).getInterface();
+ try {
+ interfaces.add(this.getParent().loadClass(clazz));
+ } catch (ClassNotFoundException e) {
+ throw new KernelException("Cant find class " + clazz
+ + " exposed by interface " + descriptor.toString()
+ + " implemented by " + abs.toString());
+ }
}
}
/* Process libraries */
- URL libraries[] = block.getLibraries();
+ URL libraries[] = abs.getLibraries();
for (int k = 0; k < libraries.length; k++) {
super.addURL(libraries[k]);
}
- String extensions[] = block.getExtendedBlocks();
+ String extensions[] = abs.getExtendedBlocks();
for (int k = 0; k < extensions.length; k++) {
- Descriptor descriptor = library.get(extensions[k]);
- if (descriptor.getType() != Descriptor.BLOCK) {
- throw new KernelException("Block " + block.toString()
- + " extends non-block " + descriptor.toString());
+ Descriptor descriptor = lib.get(extensions[k]);
+ if (descriptor.getType() == Descriptor.INTERFACE) {
+ throw new KernelException("Block " + abs.toString()
+ + " extends interface " + descriptor.toString());
}
- this.process(library, (Block) descriptor, collector, interfaces);
+ this.process(lib, (Block) descriptor, collector, interfaces);
}
}
}
