try(Connection con = getConnection()) { try (PreparedStatement prep = con.prepareConnection(“Update …”)) { //prep.doSomething(); //… //etc con.commit(); } catch (SQLException e) { //any other actions necessary on failure con.rollback(); //consider a re-throw, throwing a wrapping exception, etc } } According to the oracle documentation, you can combine a try-with-resources block with a regular try block. IMO, … Read more
Use Pacifist from http://www.charlessoft.com/ to open and install the ‘JDK 7 Update X.pkg’ in the ‘jdk7-7uX-macosx-x64.dmg’ file you download from http://www.oracle.com/technetwork/java/javase/downloads/index.html
It looks like the language in section 5.5 Casting Conversion of Java 7 JLS was updated in comparison to the same section in the Java 5/6 JLS, probably to clarify the allowed conversions. Java 7 JLS says An expression of a reference type may undergo casting conversion to a primitive type without error, by unboxing … Read more
Background MD2 was widely recognized as insecure and thus disabled in Java in version JDK 6u17 (see release notes http://www.oracle.com/technetwork/java/javase/6u17-141447.html, “Disable MD2 in certificate chain validation”), as well as JDK 7, as per the configuration you pointed out in java.security. Verisign was using a Class 3 root certificate with the md2WithRSAEncryption signature algorithm (serial 70:ba:e4:1d:10:d9:29:34:b6:38:ca:7b:03:cc:ba:bf), … Read more
For a new project select the home directory of the jdk eg C:\Java\jdk1.7.0_99 or C:\Program Files\Java\jdk1.7.0_99 For an existing project. 1) You need to have a jdk installed on the system. for instance in C:\Java\jdk1.7.0_99 2) go to project structure under File menu ctrl+alt+shift+S 3) SDKs is located under Platform Settings. Select it. 4) click … Read more
Right from the JavaDocs for java.awt.frame.setOpacity() in JDK7: The following conditions must be met in order to set the opacity value less than 1.0f: The TRANSLUCENT translucency must be supported by the underlying system The window must be undecorated (see setUndecorated(boolean) and Dialog.setUndecorated(boolean)) The window must not be in full-screen mode (see GraphicsDevice.setFullScreenWindow(Window)) If the … Read more
It seems that JDK7 process intern in a different way as before. I tested it with build 1.7.0-b147 and got “both are equal”, but when executing it (same bytecode) with 1,6.0_24 I do not get the message. It also depends where the String b2 =… line is located in the source code. The following code … Read more
Originally, this option was added to improve SPECjBB performance. The gains are due to reduced memory bandwidth requirements between the processor and DRAM. Loading and storing bytes in the byte[] consumes 1/2 the bandwidth versus chars in the char[]. However, this comes at a price. The code has to determine if the internal array is … Read more
This is how I got 1.7 to work with Eclipse. I hope it helps. I Downloaded the latest OpenJDK 1.7 universal (32/64 bits) JDK from Mac OS/X branch from http://www.oracle.com/technetwork/java/javase/downloads/jdk7-downloads-1880260.html copied the jdk to /Library/Java/JavaVirtualMachines/ next to the default 1.6.0 one In Eclipse > Preferences > Java > Installed JREs you add a new one, … Read more
The main difference from a user perspective – which I think the previous answer does not stress enough – is that Metaspace by default auto increases its size (up to what the underlying OS provides), while PermGen always has a fixed maximum size. You can set a fixed maximum for Metaspace with JVM parameters, but … Read more