String[] strings = list.toArray(new String[list.size()]); for (int i = 0; i < strings.length; i++) { System.out.println(strings[i]); } } /** 方式三:Object[] objects = list.stream().toArray(); 对结果 Object[] 不能强转 *
However, it’s not without its limitations. TheCollections.sort()method sorts in ascending order by default, and it can’t handle null values. If you try to sort a list with null values, it will throw aNullPointerException. Moreover, it may not work as expected with custom objects, unle...
> service, URL u, int line, String msg) throws ServiceConfigurationError { fail(service, u + ":" + line + ": " + msg); } // Parse a single line from the given configuration file, adding the name // on the line to the names list. // private int parseLine(Class<?> service,...
writeArray(obj, desc, unshared); }elseif(objinstanceofEnum) { writeEnum((Enum<?>) obj, desc, unshared); }elseif(objinstanceofSerializable) { writeOrdinaryObject(obj, desc, unshared);//传入流的对象第一次执行的是这个方法}else{if(extendedDebugInfo) {thrownewNotSerializableException( cl.getN...
JDK 自带的序列化,只需实现java.io.Serializable接口即可。比如下面的Student类 @NoArgsConstructor@AllArgsConstructor@Getter@Builder@ToStringpublicclassStudentimplementsSerializable{privatestaticfinallongserialVersionUID=1905122041950251207L;privateString name;privatetransientInteger age;privateString address; ...
// handle previously written and non-replaceable objects int h; if ((obj = subs.lookup(obj)) == null) { writeNull(); return; } else if (!unshared && (h = handles.lookup(obj)) != -1) { writeHandle(h); return; } else if (obj instanceof Class) { ...
Options related to string deduplication have been added to the java command tool page. String deduplication reduces the memory footprint of String objects on the Java heap by taking advantage of the fact that many String objects are identical. Instead of each String object pointing to its own ...
valueOf(42)); String s = strings.get(0); // Has compiler-generated cast } private static void unsafeAdd(List list, Object o) { list.add(o); } 因为使用了原始类型List,编译器会给出一个警告: Test.java:10: warning: [unchecked] unchecked call to add(E) as a member of the raw type...
The Java language provides special support for the string concatenation operator ( + ), and for conversion of other objects to strings. For additional information on string concatenation and conversion, see The Java™ Language Specification. Unless otherwise noted, passing a null argum...
If luaj can find a class that meets these critera, it will instantiate it, cast it to LuaFunction then call() the instance with two arguments: the modname used in the call to require(), and the environment for that function. The Java may use these values however it wishes. A typical...