![java 51.0 version java 51.0 version](https://i.stack.imgur.com/ygutF.png)
- #Java 51.0 version install
- #Java 51.0 version code
- #Java 51.0 version plus
- #Java 51.0 version download
- #Java 51.0 version windows
you have the java executable in multiple locations specified in the PATH variable, then the first one encountered when going from left to right will be the one that is executed. If you have multiple versions of Java installed - i.e. When you type java, the command shell interpreter will look through all the locations specified in the PATH variable, from left to right, to find the appropriate java runtime executable to run. The PATH environment variable tells the command shell where to look for the command you type. What is the difference between the PATH variable in JRE or JDK?
#Java 51.0 version install
Should I install the JDK, and setup my PATH variable to the JDKįor compilation, certainly, install and configure the specific JDK that you want.įor runtime, you can use the one that comes with the JDK or a standalone JRE, but regardless, make sure that you have installed the right versions and that you have configured your PATH such that there are no surprises. Javac -version for the compiler, and java -version for the runtime. You can check the versions you are currently using with use the -target parameter.Ĭ) Run your compiled classes in a JRE that is the same, or newer, version as the JDK used to compile the classes. install the appropriate JDK.ī) Compile your Java sources with the newer version of the Java compiler but in compatibility mode. compiled it) is newer.Ī) Compile your Java sources with the same, or older, version of the Java compiler as will be used to run it. Usually because the version of Java that generated your class file (i.e.
#Java 51.0 version code
This error means that the JRE that is being used to execute your class code does not recognise the version of Java used. This is not too elegant though: javac -source 1.6 -target 1.6 -bootclasspath.
#Java 51.0 version download
It looks like you can just download rt.jar from the Internet, and point to it. Like so: javac -source 1.6 -target 1.6 -bootclasspath /usr/lib/jvm/java- 6-openjdk-i386/jre/lib/rt.jar HelloWorld.java
#Java 51.0 version windows
Sorry, I don't know where it is on a Windows system). If you actually install the 1.6 JRE, you can point to its installation (for example, /usr/lib/jvm/java-6-openjdk-i386/jre/lib/rt.jar on Ubuntu, /usr/jdk/jdk1.6.0_60/jre/lib/rt.jar on SunOS apparently.
#Java 51.0 version plus
On OpenJDK javac version 1.7, you can crosscompile for 1.6 if you use parameters -source and -target, plus provide the rt.jar -file of the target version (that is, the older one) at compile time. To put it another way, there is a mismatch between source and target Java versions.Ĭhanging options in Eclipse menus don't answer the original poster, who said he/she is not using Eclipse. It needs to be "crosscompiled" for backward compatibility. However selecting the right version of Java (newer) with update-alternatives should work.Īs answered elsewhere by several people, the Java program is being run on an older version of Java than the one it was compiled it for.
![java 51.0 version java 51.0 version](https://www.fatalerrors.org/images/blog/6860ae4b1dabffc84c94b2952572f40a.jpg)
Just install appropriate Java SE Development Kit library from the Oracle site or install Jenkins There is an OpenJDK 7 package in the FreeBSD Ports collection called openjdk7 which probably needs to be reconfigured. If you want to develop Java programs then install the java-1.7.0-openjdk-devel package. The java-1.7.0-openjdk package contains just the Java Runtime Environment. Install/upgrade appropriate package via: yum install java- 1.7. Then you can install, for example: apt-get install openjdk- 7-jre Or check which are available for install: apt-cache search ^openjdk To change it, use: update-alternatives -config java To check which java (openjdk) you've installed, check via: dpkg -l "openjdk*" | grep ^i To find where SDK Java folder is located, run the following commands: jrunscript -e '.println(("")) ' Debian/Ubuntu The most common issue is misconfiguration of your JAVA_HOME variable which should point to the right Java Development Kit library, if you've multiple installed. More information about this error is available in a blog post New javac warning for setting an older source without bootclasspath. With newer versions of the Java compiler you are likely to get a warning about the bootstrap class path not being set.
![java 51.0 version java 51.0 version](https://aws1.discourse-cdn.com/codecademy/original/5X/b/3/6/8/b368c6469f1e9736a50a98aac1c6911e806f2d3f.png)
To fix the actual problem you should try to either run the Java code with a newer version of Java JRE or specify the target parameter to the Java compiler to instruct the compiler to create code compatible with earlier Java versions.įor example, in order to generate class files compatible with Java 1.4, use the following command line: javac -target 1.4 HelloWorld.java The reported major numbers are: Java SE 17 = 61, The version number shown describes the version of the JRE the class file is compatible with.