Two ways to read database configuration information (future development projects with Java link database)-------Java Fundamentals

First step: Establish Jdbc.properties first

1 User = Root 2 Password=1234563 url=mysql:jdbc://localhost:3306  /yanlong4 driver=Com.mysql.jdbc.Driver

View CodeThe first way: direct file read

1  Packagecom.mon11.day14;2 3 ImportJava.io.File;4 ImportJava.io.FileInputStream;5 Importjava.io.FileNotFoundException;6 ImportJava.io.InputStream;7 Importjava.util.Properties;8 9 /** Ten * Class Description: 1. Read directly from the file One * @authorAuthor: Administrator A * @versionCreation Date: November 14, 2017 - */ -  Public classtestproperties { the  -      Public Static voidMain (string[] args) { -         /*The Propertiesproperties class represents a persistent set of properties.  - Properties can be saved in a stream or loaded from a stream.  + each key and its corresponding value in the property list is a string. */  -          +Properties properties=NewProperties ();//instantiating an object A          atFile file=NewFile ("Src/jdbc.properties");//Open File -          -         Try { -InputStream inputstream=NewFileInputStream (file);//Open the file's interface - properties.load (inputstream); -}Catch(Exception e) { in             //TODO auto-generated Catch block - e.printstacktrace (); to         } +          -         //Output theSystem.out.println (Properties.get ("User")); *System.out.println (Properties.get ("Password")); $System.out.println (properties.get ("url"));Panax NotoginsengSystem.out.println (Properties.get ("Driver")); -          the     } +}

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Second way: Read through the ClassLoader (project development with this, large project)

1  Packagecom.mon11.day14;2 3 ImportJava.io.File;4 ImportJava.io.FileInputStream;5 Importjava.io.FileNotFoundException;6 Importjava.io.IOException;7 ImportJava.io.InputStream;8 Importjava.util.Properties;9 Ten /**  One * Class Description: 1. Direct class loader Read A * @authorAuthor: Administrator - * @versionCreation Date: November 14, 2017 - */ the  Public classTestProperties2 { -  -      Public Static voidMain (string[] args) { -         /*The Propertiesproperties class represents a persistent set of properties.  + Properties can be saved in a stream or loaded from a stream.  - each key and its corresponding value in the property list is a string. */  +          AProperties properties=NewProperties ();//instantiating an object at          -         //loading through the class loader -         Try { -Properties.load (TestProperties2.class. getClassLoader (). getResourceAsStream ("Jdbc.properties")); -             //getClassLoader () returns the class loader for this class.  -             //getResourceAsStream (String name) finds the resource with the given name.  in}Catch(IOException e) { -             //TODO auto-generated Catch block to e.printstacktrace (); +         } -         //Output theSystem.out.println (Properties.get ("User")); *System.out.println (Properties.get ("Password")); $System.out.println (properties.get ("url"));Panax NotoginsengSystem.out.println (Properties.get ("Driver")); -          the     } +}

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Two ways to read database configuration information (future development projects with a Java linked database)-------Java Fundamentals