java-5

问题 Casting, instanceof, and @SuppressWarnings("unchecked") are noisy. It would be nice to stuff them down into a method where they won't need to be looked at. CheckedCast.castToMapOf() is an attempt to do that. castToMapOf() is making some assumptions: (1) The map can't be trusted to be homogeneous (2) Redesigning to avoid need for casting or instanceof is not viable (3) Ensuring type safety in an fail early manner is more important than the performance hit (4) Returning Map<String,String> is

问题 First of all, according to the documentation, the JAX-WS reference implementation is supposed to work with Java 5. The binary package with the latest version (2.2.7) is however compiled with Java 6 (class version 50.0), so using it with Java 5 will cause an UnsupportedClassVersionError to be thrown. I've downloaded the Java sources and tried to compile them with Java 5, but since dependent libraries are compiled for Java 6, this does not work directly either. I've tried to compile a new

问题 We are using JBoss_4_0_4_GA with JDK 1.5.0 (no updates) on a Windows The JBoss server is run within a Wrapper (Version 3.2.3) http://wrapper.tanukisoftware.org. Since the JVM is so old I cannot even use the -XX:+HeapDumpOnOutOfMemoryError option on the JVM. What are my option to find out the issue? As usual the Out of Memory exception is happening on different parts of the application. I do not have the liberty to upgrade the JVM right away. The current VM settings Java Additional Parameters

问题 I am using the below code to upload image. The problem is that after uploading the image i cant change the file permission. my file permission set by default is rw-r--r-- ( 0644 ). Is it possible to change the file permission or set it as 0777 by default? It works fine in my local system. But not able to change the permission in my linux server. <% try { int filesize=0; String fieldname="",fieldvalue="",filename="",content="",bookid="",bkdescription=""; try { List<FileItem> items = new

问题 I get this error: java.lang.InternalError: name is too long to represent at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:621) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124) at weblogic.utils.classloaders.GenericClassLoader.defineClass(GenericClassLoader.java:338) at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:291) at weblogic.utils.classloaders.GenericClassLoader

问题 I get this error: java.lang.InternalError: name is too long to represent at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:621) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124) at weblogic.utils.classloaders.GenericClassLoader.defineClass(GenericClassLoader.java:338) at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:291) at weblogic.utils.classloaders.GenericClassLoader

问题 I'm trying to read the emails in a folder of an email account Office365 using JavaMail 1.4 api. My code is: public static void main(String argv[]) throws Exception { // Get a Properties object Properties props = System.getProperties(); // Get a Session object Session session = Session.getInstance(props, null); // Get a Store object Store store = null; Folder rf = null; if (CUR_MAIL_PROTOCOL != null) store = session.getStore("imap"); // Connect if (CUR_MAIL_HOST != null || CUR_MAIL_LOGIN !=

问题 I'm trying to read the emails in a folder of an email account Office365 using JavaMail 1.4 api. My code is: public static void main(String argv[]) throws Exception { // Get a Properties object Properties props = System.getProperties(); // Get a Session object Session session = Session.getInstance(props, null); // Get a Store object Store store = null; Folder rf = null; if (CUR_MAIL_PROTOCOL != null) store = session.getStore("imap"); // Connect if (CUR_MAIL_HOST != null || CUR_MAIL_LOGIN !=

问题 I've recently moved to Java 7 in one of my projects. I claim that it can run on Java 1.5 simply because there's nothing I depend on that is in Java 6 or 7. However when compiling today I noticed this: bootstrap class path not set in conjunction with -source 1.5 Google has found little information on this warning. Does this mean that you can't compile to Java 1.5 from Java 1.7? 回答1: This Oracle blog explains the warning: http://blogs.oracle.com/darcy/entry/bootclasspath_older_source The reason

问题 Since Java 5 it is said that the best way to create a singleton is by a single-element enum type. Example: public enum SuperSingleton implements Zooma{ INSTANCE; /** */ public void fightTheBattle(){ System.out.println("I am fighting the battle!!!"); } @Override public void runningWild() { //This is method implemented from the Zooma interface. } } According to Joshua Bloch, the single-element enum type singleton is; more concise provides the serialization machinery for free and provides an