java-7

问题 I had the following issue recently in my code. The environment is: Java(TM) SE Runtime Environment (build pap6470sr1-20120330_01(SR1)) IBM J9 VM (build 2.6, JRE 1.7.0 AIX ppc64-64 20120322_106209 (JIT enabled, AOT enabled)) J9VM - R26_Java726_SR1_20120322_1720_B106209 Throwable occurred: java.lang.ArrayIndexOutOfBoundsException: Array index out of range: -14 at com.sun.xml.bind.v2.util.CollisionCheckStack.findDuplicate(CollisionCheckStack.java:133) at com.sun.xml.bind.v2.util

问题 is there any way to use java 7 syntax and produce bytecode that works on 1.5? as far as i know, options -target and -source can't be different. checking if no new API was used also would be nice but is not crucial 回答1: No, it is not. As far as I know, different -source and -target work, but only if the source is lower or equal the target (in order to provide backwards compatibility). There may be source converters that convert your java 7 code into older versions. 回答2: There's a project

问题 I'm having trouble using the official Maven Plugin and Java 7 with Google Appengine. Configuration My project configuration pom.xml is quite simple: In the properties section I configure: <gae.version>1.7.4</gae.version> And later on I use the plugin: <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>2.3.2</version> <configuration> <source>1.7</source> <target>1.7</target> </configuration> </plugin> <plugin> <groupId>com.google

问题 How to modify Java Control Panel selections (corresponding to deployment.properties file) from windows command prompt? Specifically, I am looking for command(s) which can effect change in "Action for local applets" selection, in "Custom Security Level Settings" window (click the "Settings..." button next to "Custom" setting for the "Security Level" slider in the Security tab in Java Control Panel) , from "Prompt user" to "Run without prompt" . This setting's default value changed with update

问题 I have a problem , my android-sdk-manager is suddenly stopped showing all packages, it is only showing the installed packages only. Can you guys help me out how to solve this issue? 回答1: Navigate through File --> setting --> Android SDK --> SDK update site tab, in that check force https://... sources to be fetched using http://... 回答2: Firstly, just try toggling " Updates/New ", there might be a glitch on the SDK manager itself. Secondly you can go to " Tools -> Manage Add On sites... "

问题 According to Oracle's online documentation, JnlpDownloadServlet is still a part of Java 7: http://docs.oracle.com/javase/7/docs/technotes/guides/javaws/developersguide/downloadservletguide.html But I just installed JDK 1.7.0, and neither jnlp-servlet.jar nor jardiff.jar appear anywhere in my Java home, at least on Windows. I ran a search through every jar in the directory (using the excellent ack command-line utility) and none of them contain JnlpDownloadServlet. 回答1: Starting with Java 7

问题 Java 7 defines this option, yet I fail to understand its usefulness.Consider this simple program, run on a recent enough Linux machine, with a Java 6 JVM: public static void main(final String... args) throws IOException { final long offset = 1L << 31; final RandomAccessFile f = new RandomAccessFile("/tmp/foo", "rw"); f.seek(offset); f.writeInt(2); f.close(); } When I query the file "shell wise", I get, as expected: $ cd /tmp $ stat --format %s foo 2147483652 $ du --block-size=1 foo 4096 foo

问题 I'm recursively watching a directory (and therefore all subdirs and files) for changes. It seems, if I'm creating or deleting a directory or file in a subdirectory of the root-dir to watch the Path which is included in the WatchEvent instance one receives (via context()) has no Parent and therefore rootDirToWatch.resolve(event.context()) is not returning the Path I like to have. For instance: /home/johannes/test is watched, then I'm creating a new directory in /home/johannes/test/foo/bar

问题 I have try to run my play application in PROD mode with Java 7 and I was surprised. Precompiling fails: 10:28:18,819 INFO ~ Precompiling ... # # A fatal error has been detected by the Java Runtime Environment: # # SIGSEGV (0xb) at pc=0xb6ed766c, pid=27336, tid=2673077104 # # JRE version: 7.0_01-b08 # Java VM: Java HotSpot(TM) Server VM (21.1-b02 mixed mode linux-x86 ) # Problematic frame: # V [libjvm.so+0x4fc66c] PhaseIdealLoop::build_loop_late_post(Node*)+0x15c # # Failed to write core dump.

问题 Will structs and value types (like C#'s) be included in Java 7? 回答1: Not that I've seen in any proposals - and I'm pretty sure we'd have heard about it by now. Note that this would be a very significant JVM change, rather than just a language change as many of the existing proposals are. 回答2: Here is John Rose's (an Oracle JVM developer) blog post about this proposal. It has been around for a while, but not as an official JSR. It seems unlikely to happen even in java 9. http://blogs.oracle