| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.iapi.services.io.FormatableHashtable |
| 4 | |
| 5 | Copyright 1999, 2004 The Apache Software Foundation or its licensors, as applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | |
| 21 | package org.apache.derby.iapi.services.io; |
| 22 | |
| 23 | import org.apache.derby.iapi.services.io.ArrayInputStream; |
| 24 | |
| 25 | import org.apache.derby.iapi.services.io.StoredFormatIds; |
| 26 | import org.apache.derby.iapi.services.io.FormatIdUtil; |
| 27 | import org.apache.derby.iapi.services.io.Formatable; |
| 28 | import org.apache.derby.iapi.services.sanity.SanityManager; |
| 29 | |
| 30 | import java.util.Hashtable; |
| 31 | import java.util.Enumeration; |
| 32 | import java.io.ObjectOutput; |
| 33 | import java.io.ObjectInput; |
| 34 | import java.io.IOException; |
| 35 | |
| 36 | |
| 37 | /** |
| 38 | * A formatable holder for a java.util.Hashtable. |
| 39 | * Used to avoid serializing Properties. |
| 40 | */ |
| 41 | public class FormatableHashtable extends Hashtable implements Formatable |
| 42 | { |
| 43 | /******************************************************** |
| 44 | ** |
| 45 | ** This class implements Formatable. That means that it |
| 46 | ** can write itself to and from a formatted stream. If |
| 47 | ** you add more fields to this class, make sure that you |
| 48 | ** also write/read them with the writeExternal()/readExternal() |
| 49 | ** methods. |
| 50 | ** |
| 51 | ** If, inbetween releases, you add more fields to this class, |
| 52 | ** then you should bump the version number emitted by the getTypeFormatId() |
| 53 | ** method. |
| 54 | ** |
| 55 | ********************************************************/ |
| 56 | |
| 57 | /** |
| 58 | * Niladic constructor for formatable |
| 59 | */ |
| 60 | public FormatableHashtable() |
| 61 | { |
| 62 | } |
| 63 | |
| 64 | |
| 65 | /** |
| 66 | * Our special put method that wont barf |
| 67 | * on a null value. |
| 68 | * @see java.util.Hashtable |
| 69 | */ |
| 70 | public Object put(Object key, Object value) |
| 71 | { |
| 72 | if (value == null) |
| 73 | { |
| 74 | return remove(key); |
| 75 | } |
| 76 | |
| 77 | if (SanityManager.DEBUG) { |
| 78 | |
| 79 | if ((value instanceof FormatableIntHolder) || |
| 80 | (value instanceof FormatableLongHolder) || |
| 81 | ((value instanceof java.io.Serializable) && (!(value instanceof Formatable)) && (!(value instanceof String))) |
| 82 | ) { |
| 83 | |
| 84 | if (!value.getClass().isArray()) { |
| 85 | |
| 86 | // System.out.println("key " + key + " class " + value.getClass()); |
| 87 | //new Throwable().printStackTrace(System.out); |
| 88 | //System.exit(1); |
| 89 | } |
| 90 | } |
| 91 | } |
| 92 | return super.put(key, value); |
| 93 | } |
| 94 | |
| 95 | public void putInt(Object key, int value) { |
| 96 | |
| 97 | super.put(key, new FormatableIntHolder(value)); |
| 98 | } |
| 99 | |
| 100 | public int getInt(Object key) { |
| 101 | |
| 102 | return ((FormatableIntHolder) get(key)).getInt(); |
| 103 | } |
| 104 | public void putLong(Object key, long value) { |
| 105 | |
| 106 | super.put(key, new FormatableLongHolder(value)); |
| 107 | } |
| 108 | |
| 109 | public long getLong(Object key) { |
| 110 | |
| 111 | return ((FormatableLongHolder) get(key)).getLong(); |
| 112 | } |
| 113 | public void putBoolean(Object key, boolean value) { |
| 114 | |
| 115 | putInt(key,value ? 1 : 0); |
| 116 | } |
| 117 | |
| 118 | public boolean getBoolean(Object key) { |
| 119 | |
| 120 | return getInt(key) == 0 ? false : true; |
| 121 | |
| 122 | } |
| 123 | |
| 124 | ////////////////////////////////////////////// |
| 125 | // |
| 126 | // FORMATABLE |
| 127 | // |
| 128 | ////////////////////////////////////////////// |
| 129 | /** |
| 130 | * Write the hash table out. Step through |
| 131 | * the enumeration and write the strings out |
| 132 | * in UTF. |
| 133 | * |
| 134 | * @param out write bytes here |
| 135 | * |
| 136 | * @exception IOException thrown on error |
| 137 | */ |
| 138 | public void writeExternal(ObjectOutput out) throws IOException |
| 139 | { |
| 140 | out.writeInt(size()); |
| 141 | for (Enumeration e = keys(); e.hasMoreElements(); ) |
| 142 | { |
| 143 | Object key = e.nextElement(); |
| 144 | out.writeObject(key); |
| 145 | out.writeObject(get(key)); |
| 146 | |
| 147 | if (SanityManager.DEBUG) |
| 148 | { |
| 149 | Object value = get(key); |
| 150 | if (value instanceof Formatable[]) |
| 151 | { |
| 152 | SanityManager.THROWASSERT("you should be using FormatableArrayHolder rather than writing out an array of Formatables, otherwise you will get bad behavior for null Storables. Your class is a "+value.getClass().getName()); |
| 153 | } |
| 154 | } |
| 155 | } |
| 156 | } |
| 157 | |
| 158 | /** |
| 159 | * Read the hash table from a stream of stored objects. |
| 160 | * |
| 161 | * @param in read this. |
| 162 | * |
| 163 | * @exception IOException thrown on error |
| 164 | * @exception ClassNotFoundException thrown on error |
| 165 | */ |
| 166 | public void readExternal(ObjectInput in) |
| 167 | throws IOException, ClassNotFoundException |
| 168 | { |
| 169 | int size = in.readInt(); |
| 170 | for (; size > 0; size--) |
| 171 | { |
| 172 | super.put(in.readObject(), in.readObject()); |
| 173 | } |
| 174 | } |
| 175 | public void readExternal(ArrayInputStream in) |
| 176 | throws IOException, ClassNotFoundException |
| 177 | { |
| 178 | int size = in.readInt(); |
| 179 | for (; size > 0; size--) |
| 180 | { |
| 181 | super.put(in.readObject(), in.readObject()); |
| 182 | } |
| 183 | } |
| 184 | |
| 185 | /** |
| 186 | * Get the formatID which corresponds to this class. |
| 187 | * |
| 188 | * @return the formatID of this class |
| 189 | */ |
| 190 | public int getTypeFormatId() { return StoredFormatIds.FORMATABLE_HASHTABLE_V01_ID; } |
| 191 | } |