--- /dev/null
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ * VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.utils.datastructures.collections;\r
+\r
+import java.util.Arrays;\r
+\r
+\r
+public class LightweightList {\r
+\r
+ public static final Object EMPTY = new LL0();\r
+ \r
+ public static Object add(Object list, Object value) {\r
+ if(list instanceof LL)\r
+ return ((LL)list).add(value);\r
+ else\r
+ return new LL2(list, value);\r
+ }\r
+ \r
+ public static Object remove(Object list, Object value) {\r
+ if(list instanceof LL)\r
+ return ((LL)list).remove(value);\r
+ else\r
+ return value.equals(list) ? EMPTY : list;\r
+ }\r
+\r
+ public static int size(Object list) {\r
+ if(list instanceof LL)\r
+ return ((LL)list).size();\r
+ else\r
+ return 1;\r
+ }\r
+ \r
+ public static boolean isEmpty(Object list) {\r
+ return list==EMPTY;\r
+ } \r
+ \r
+ public static Object[] toArray(Object list) {\r
+ if(list == null)\r
+ return EMPTY_ARRAY;\r
+ else if(list instanceof LL)\r
+ return ((LL)list).toArray();\r
+ else\r
+ return new Object[] { list };\r
+ }\r
+ \r
+ public static interface IProcedure {\r
+ void exec(Object obj);\r
+ }\r
+ \r
+ public static void forEach(Object list, IProcedure proc) {\r
+ if(list == null)\r
+ return;\r
+ else if(list instanceof LL)\r
+ ((LL)list).forEach(proc);\r
+ else\r
+ proc.exec(list);\r
+ }\r
+ \r
+ private static interface LL {\r
+ Object add(Object value);\r
+ Object remove(Object value);\r
+ int size();\r
+ Object[] toArray();\r
+ void forEach(IProcedure proc);\r
+ }\r
+ \r
+ static final Object[] EMPTY_ARRAY = new Object[0];\r
+ private static class LL0 implements LL { \r
+\r
+ @Override\r
+ public Object add(Object value) {\r
+ return value;\r
+ }\r
+\r
+ @Override\r
+ public Object remove(Object value) {\r
+ return this;\r
+ }\r
+\r
+ @Override\r
+ public int size() {\r
+ return 0;\r
+ }\r
+\r
+ @Override\r
+ public Object[] toArray() {\r
+ return EMPTY_ARRAY;\r
+ }\r
+\r
+ @Override\r
+ public void forEach(IProcedure proc) {\r
+ }\r
+ \r
+ }\r
+ \r
+ private static class LL2 implements LL {\r
+\r
+ Object v0, v1; \r
+ \r
+ public LL2(Object v0, Object v1) {\r
+ this.v0 = v0;\r
+ this.v1 = v1;\r
+ }\r
+\r
+ @Override\r
+ public Object add(Object value) {\r
+ return new LL3(v0, v1, value);\r
+ }\r
+\r
+ @Override\r
+ public Object remove(Object value) {\r
+ if(value.equals(v0))\r
+ return v1;\r
+ else if(value.equals(v1))\r
+ return v0;\r
+ else\r
+ return this;\r
+ }\r
+\r
+ @Override\r
+ public int size() {\r
+ return 2;\r
+ }\r
+\r
+ @Override\r
+ public Object[] toArray() {\r
+ return new Object[] { v0, v1 };\r
+ }\r
+\r
+ @Override\r
+ public void forEach(IProcedure proc) {\r
+ proc.exec(v0);\r
+ proc.exec(v1);\r
+ }\r
+ \r
+ }\r
+ \r
+ private static class LL3 implements LL {\r
+\r
+ Object v0, v1, v2; \r
+ \r
+ public LL3(Object v0, Object v1, Object v2) {\r
+ this.v0 = v0;\r
+ this.v1 = v1;\r
+ this.v2 = v2;\r
+ }\r
+\r
+ @Override\r
+ public Object add(Object value) {\r
+ return new LLN(v0, v1, v2, value);\r
+ }\r
+\r
+ @Override\r
+ public Object remove(Object value) {\r
+ if(value.equals(v0))\r
+ return new LL2(v1, v2);\r
+ else if(value.equals(v1))\r
+ return new LL2(v0, v2);\r
+ else if(value.equals(v2))\r
+ return new LL2(v0, v1);\r
+ else\r
+ return this;\r
+ }\r
+\r
+ @Override\r
+ public int size() {\r
+ return 3;\r
+ }\r
+ \r
+ @Override\r
+ public Object[] toArray() {\r
+ return new Object[] { v0, v1, v2 };\r
+ }\r
+ \r
+ @Override\r
+ public void forEach(IProcedure proc) {\r
+ proc.exec(v0);\r
+ proc.exec(v1);\r
+ proc.exec(v2);\r
+ }\r
+ }\r
+ \r
+ private static class LLN implements LL {\r
+\r
+ Object[] array;\r
+ int size;\r
+ \r
+ public LLN(Object v0, Object v1, Object v2, Object v3) {\r
+ array = new Object[] { v0, v1, v2, v3, null, null };\r
+ size = 4;\r
+ }\r
+\r
+ @Override\r
+ public Object add(Object value) {\r
+ if(size==array.length)\r
+ array = Arrays.copyOf(array, (size*3)/2+1); \r
+ array[size++] = value;\r
+ return this;\r
+ }\r
+\r
+ @Override\r
+ public Object remove(Object value) {\r
+ for(int i=0;i<size;++i) {\r
+ if(value.equals(array[i])) {\r
+ while(i < size-1) { \r
+ array[i] = array[i+1];\r
+ ++i;\r
+ }\r
+ array[--size] = null;\r
+ if(size == 3)\r
+ return new LL3(array[0], array[1], array[2]);\r
+ else\r
+ return this;\r
+ }\r
+ }\r
+ return this; \r
+ }\r
+\r
+ @Override\r
+ public int size() {\r
+ return size;\r
+ }\r
+ \r
+ @Override\r
+ public Object[] toArray() {\r
+ return Arrays.copyOf(array, size);\r
+ }\r
+ \r
+ @Override\r
+ public void forEach(IProcedure proc) {\r
+ for(int i=0;i<size;++i)\r
+ proc.exec(array[i]);\r
+ }\r
+ } \r
+ \r
+}\r
Code Review / simantics / platform.git / blobdiff