Use java's StringBuilder.insert() function to insert a string at the specified position

TestthePDFinanotherapptodetermineiftheissueiswiththefileorEdge.2.Enablethebuilt-inPDFviewerbyturningoff"AlwaysopenPDFfilesexternally"and"DownloadPDFfiles"inEdgesettings.3.Clearbrowsingdataincludingcookiesandcachedfilestoresolveren

Run the child process using the os/exec package, create the command through exec.Command but not execute it immediately; 2. Run the command with .Output() and catch stdout. If the exit code is non-zero, return exec.ExitError; 3. Use .Start() to start the process without blocking, combine with .StdoutPipe() to stream output in real time; 4. Enter data into the process through .StdinPipe(), and after writing, you need to close the pipeline and call .Wait() to wait for the end; 5. Exec.ExitError must be processed to get the exit code and stderr of the failed command to avoid zombie processes.

Method overloading and method overloading are two mechanisms for implementing polymorphism in Java. 1. Method overload occurs in the same class. It requires the same method name but different parameter list (number, type or order of parameters), which belongs to compile-time polymorphism. The return type can be different but cannot be overloaded by the return type alone. There can be different access modifiers and exception declarations; 2. Method rewriting occurs in the inheritance relationship. The subclass provides the specific implementation of the existing methods of the parent class. It requires the same method signature and the return type is compatible. The access modifier cannot be more strict. It belongs to the runtime polymorphism. The instance method must be used and the correct rewrite can be ensured through the @Override annotation. Together, the two improve code readability and scalability.

To optimize nested foreach loops, redundant iterations should be avoided first, and the time complexity can be reduced from O(n×m) to O(n m); second, if the structure is not truly hierarchical, the data should be flattened using methods such as SelectMany; third, jump out in advance or skip unnecessary processing through conditional judgment; fourth, select appropriate data structures such as dictionary or hash sets to improve search efficiency; fifth, parallelization can be used with caution when operations are independent and time-consuming; sixth, extract complex logic into independent methods or queries to improve readability and maintainability. The core of optimization is to reduce complexity, organize data reasonably, and always evaluate the necessity of nesting, ultimately achieving efficient, clear and extensible code.

Containerized Java application: Create a Dockerfile, use a basic image such as eclipse-temurin:17-jre-alpine, copy the JAR file and define the startup command, build the image through dockerbuild and run locally with dockerrun. 2. Push the image to the container registry: Use dockertag to mark the image and push it to DockerHub and other registries. You must first log in to dockerlogin. 3. Deploy to Kubernetes: Write deployment.yaml to define the Deployment, set the number of replicas, container images and resource restrictions, and write service.yaml to create

isdigit() is only applicable to positive integers, and does not support decimals, negative numbers and scientific notation methods; 2. isnumeric() supports more Unicode numbers such as fractions, but still does not support decimal points and negative signs; 3. Replace combined with isdigit can judge integers and decimals, but does not support scientific notation methods; 4. try-except try float conversion is the most general method, supporting integers, decimals, negative numbers and scientific notation methods, and is recommended for general scenarios; 5. Regular expressions can accurately control the number format, but are complicated to write and prone to errors; Summary: The most practical method is the fourth method, which is simple and comprehensively supports various numeric forms, ending with a complete sentence.

Importjava.ioandjava.net.SocketforI/Oandsocketcommunication.2.CreateaSocketobjecttoconnecttotheserverusinghostnameandport.3.UsePrintWritertosenddataviaoutputstreamandBufferedReadertoreadserverresponsesfrominputstream.4.Usetry-with-resourcestoautomati

In VSCode, you can quickly switch the panel and editing area through shortcut keys. To jump to the left Explorer panel, use Ctrl Shift E (Windows/Linux) or Cmd Shift E (Mac); return to the editing area to use Ctrl ` or Esc or Ctrl 1~9. Compared to mouse operation, keyboard shortcuts are more efficient and do not interrupt the encoding rhythm. Other tips include: Ctrl KCtrl E Focus Search Box, F2 Rename File, Delete File, Enter Open File, Arrow Key Expand/Collapse Folder.