如果你使用的是Java 6，则可以尝试使用Java Compiler API。其核心是JavaCompiler类。你应该能够
Comparator在内存中构造对象的源代码。
警告：由于某些奇怪的原因，我的平台上不存在JavaCompiler对象，因此我实际上并未尝试下面的代码…
警告：编译任意Java代码可能会危害你的健康。
考虑一下自己被警告…
String comparableClassName = ...; // the class name of the objects you wish to compareString comparatorClassName = ...; // something random to avoid class name conflictsString source = "public class " + comparatorClassName + " implements Comparable<" + comparableClassName + "> {" + " public int compare(" + comparableClassName + " a, " + comparableClassName + " b) {" + " return " + expression + ";" + " }" + "}";JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();Writer out = null;JavaFileManager fileManager = null;DiagnosticListener<? super JavaFileObject> diagnosticListener = null;Iterable<String> options = null;Iterable<String> classes = null;Iterable<? extends JavaFileObject> compilationUnits = new ArrayList<? extends JavaFileObject>();compilationUnits.add( new SimpleJavaFileObject() { // See the JavaDoc page for more details on loading the source String });compiler.getTask(out, fileManager, diagnosticListener, options, classes, compilationUnits).call();Comparator comparator = (Comparator) Class.forName(comparableClassName).newInstance();之后，你只需要在数据库字段中存储适当的Java表达式，
a并引用和即可b。
