我正在尝试使用 XStream 将数据库保存到文件中，然后稍后使用 XStream 再次打开它并将其反序列化回它之前所在的对象。数据库由表的arraylist 组成，它由数据类的arraylist 组成，其中数据类包含对象的arraylist。我基本上是在尝试创建一个 sql 编译器。由于 load 方法的最后一行，我目前收到 java.lang.NoSuchMethodError 。这是我所拥有的：
保存方法
public void save(Database DB){
File file = new File(DB.getName().toUpperCase() + ".xml");
//Test sample
DB.createTable("TBL1(character(a));");
DB.tables.getTable("TBL1").rows.add(new DataList());
DB.tables.getTable("TBL1").rows.getRow(0).add(10);
XStream xstream = new XStream();
//Database
xstream.alias("Database", Database.class);
//Tables
xstream.alias("Table", Table.class);
//Rows
xstream.alias("Row", DataList.class);
//Data
//xstream.alias("Data", Object.class);
//String xml = xstream.toXML(DB);
Writer writer = null;
try {
writer = new FileWriter(file);
writer.write(xstream.toXML(DB));
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
加载方法
public void Load(String dbName){
XStream xstream = new XStream();
BufferedReader br;
StringBuffer buff = null;
try {
br = new BufferedReader(new FileReader(dbName + ".xml"));
buff = new StringBuffer();
String line;
while((line = br.readLine()) != null){
buff.append(line);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
database = (Database)xstream.fromXML(buff.toString());
}
堆栈跟踪
Exception in thread "main" java.lang.NoSuchMethodError:
org.xmlpull.v1.XmlPullParserFactory.newInstance(Ljava/lang/String;Ljava/lang/Class;)Lorg/xmlpull/v1/XmlPullParserFactory;
at com.thoughtworks.xstream.io.xml.XppDriver.createParser(XppDriver.java:57)
at com.thoughtworks.xstream.io.xml.AbstractXppDriver.createReader(AbstractXppDriver.java:54)
at com.thoughtworks.xstream.XStream.fromXML(XStream.java:913)
at com.thoughtworks.xstream.XStream.fromXML(XStream.java:904)
at dbt.Load(dbt.java:255)
at dbt.checktypestatement(dbt.java:88)
at dbt.main(dbt.java:45)
更改一些库（参考库：xstream、xpp3 和 xmlpull）后，这是我在运行时遇到的错误：
Exception in thread "main" com.thoughtworks.xstream.converters.ConversionException: Row : Row
---- Debugging information ----
message : Row
cause-exception : com.thoughtworks.xstream.mapper.CannotResolveClassException
cause-message : Row
class : java.util.ArrayList
required-type : java.util.ArrayList
converter-type : com.thoughtworks.xstream.converters.collections.CollectionConverter
path : /Database/tables/tables/Table/rows/rows/Row
line number : 1
class[1] : RowList
converter-type[1] : com.thoughtworks.xstream.converters.reflection.ReflectionConverter
class[2] : Table
class[3] : TableList
class[4] : Database
version : null
-------------------------------
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:79)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshallField(AbstractReflectionConverter.java:355)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doUnmarshal(AbstractReflectionConverter.java:306)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:234)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshallField(AbstractReflectionConverter.java:355)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doUnmarshal(AbstractReflectionConverter.java:306)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:234)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at com.thoughtworks.xstream.converters.collections.AbstractCollectionConverter.readItem(AbstractCollectionConverter.java:71)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.addCurrentElementToCollection(CollectionConverter.java:79)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.populateCollection(CollectionConverter.java:72)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.populateCollection(CollectionConverter.java:66)
at com.thoughtworks.xstream.converters.collections.CollectionConverter.unmarshal(CollectionConverter.java:61)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshallField(AbstractReflectionConverter.java:355)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doUnmarshal(AbstractReflectionConverter.java:306)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:234)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshallField(AbstractReflectionConverter.java:355)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.doUnmarshal(AbstractReflectionConverter.java:306)
at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:234)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:134)
at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:32)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1058)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1042)
at com.thoughtworks.xstream.XStream.fromXML(XStream.java:913)
at com.thoughtworks.xstream.XStream.fromXML(XStream.java:904)
at dbt.load(dbt.java:257)
at dbt.checktypestatement(dbt.java:87)
at dbt.main(dbt.java:44)
Caused by: com.thoughtworks.xstream.mapper.CannotResolveClassException: Row
at com.thoughtworks.xstream.mapper.DefaultMapper.realClass(DefaultMapper.java:56)
at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30)
at com.thoughtworks.xstream.mapper.DynamicProxyMapper.realClass(DynamicProxyMapper.java:55)
...