→ Refer to the code for Gradle 2.x of the predecessor, and refer to the Gradle 5.x compatible version
Copy source jar files into directory (Qiita ) Posted in

Generate a .classpath file

A configuration file that allows the IDE to load jars and source code. Originally for Eclipse, it also supports InteliJ IDEA.

I want to maintain this file with Gradle because it's a big deal.

It can be generated just by applying Gradle's ʻeclipse` plugin ...

.classpath Absolute path problem

The path in .classpath generated by Plugin is an absolute path. It is inconvenient because it becomes an environment-dependent path and cannot be shared with Git.

solution: --Create .classpath each time by gradle eclipseClasspath at your own hands -: -1: It takes time for everyone to do it every time -: -1: The reproducibility of the build decreases (even though it worked at hand! Phenomenon) --Generate .classpath in relative path notation with Gradle and commit with jar file -: + 1: Just execute it together with a copy of the Jar file etc. OK

Generate .classpath in relative path notation

ʻEclipseplugin'spathVariables'.': Instead of projectDir`, if you extend it using the plugin hook as shown in Reference site good:

eclipse.classpath.file {
    whenMerged { classpath ->
        classpath.entries.findAll { entry -> entry.kind == 'lib' }.each {
            it.path = it.path.replaceFirst("${projectDir.absolutePath}/", '')
            it.exported = false
        }
    }
}

ʻEclipse.classpath.file`` whenMerged`

You can freely control the contents of the .classpath file with whenMerged

For example:

--Rewrite the reference path of the jar file with arbitrary logic --In our case, only some files are placed in different directories. -- classpath.entries.sort controls the sort order of .classpath --Useful for load-order-dependent library measures such as JMockit --classpath.getEntries (). removeAll {return (conditional expression)} --You can exclude jars that you don't want the IDE to load

Change of jar file name

Manual management jar filenames and Gradle-derived jars often do not match. For example:

--Manually managed file name: crimson.jar --Gradle download result: crimson-1.1.3.jar

There is a problem when referencing with a fixed file name. In particular, there are the following:

--A fixed file name in the classpath of build tools such as Ant --File name fixed in the classpath option of the JVM when the program starts

Workaround for jar file name change

1. (Not recommended) Rename to the old file name in post-processing -: -1: Accident when the name of the rename source group or artifact changes -: -1: I'm having trouble dealing with new jars
2. Be unaware of individual libraries -: + 1: Design OK just by reading all the jars under a specific directory --Leverage * wildcards in Ant, JVM classpath (> = 6), shell, etc. --Note that the interpretation of * is slightly different.

The latter is a hassle, but it is a temporary effort, so it is better to deal with it in the long run.

<!-==================================== # Section: Strategy Part (Jar Management) = ===================================->

Package management tool implementation technique: Managing jars for various reasons

~ Techniques for handling jar files that came from beyond history ~

Common things in old jar files

<! ---- The jar contained in the all-in-one jar is squishy->

--I was able to get the jar again, but the binaries do not match --SNAPSHOT version --Although it is non-SNAPSHOT, it has been replaced and released. --Different binaries are placed between Maven repositories --Original patch of unknown background: imp: --The official page has disappeared and you cannot re-obtain the jar or source

Find out what caused the jar binary mismatch

Don't leave the discrepancy, just check the specific differences:

--You can limit the scope and risk of introducing a package management tool. --The range to be tested and the test method will be clarified.

I issued a SHA-1 hash of the jar file before and after Gradle conversion, We examined the specific differences for jars whose hashes do not match.

How to check the difference of jar file

The jar file is a zip and when unzipped you will see the following files:

1. .class file (Java bytecode)
2. Metadata files such as META-INF
3. Other resource files such as property files

Except for .class, most text comparison tools can be used for comparison.

Example when there is a difference in META-INF / MANIFEST.MF of lucene-analyzers-2.4.0: </ small>

8c8
< Implementation-Version: 2.4.0 701827 - 2008-10-05 16:46:27
> Implementation-Version: 2.4.0 701827 - 2008-10-05 16:44:47

2c2
< final class com.google.inject.servlet.ServletScopes$1 implements com.google.inject.Scope {
> class com.google.inject.servlet.ServletScopes$1 implements com.google.inject.Scope {

repositories {
  maven {
    url 'http://central.maven.org/maven2/'    
  } // mavenCentral()I do not dare to use the abbreviated notation(See below)

  maven {
    url "http://URL of a private repository"
  }
}

<project>
  <modelVersion>4.0.0</modelVersion>

  <!--Identification information for this jar itself-->
  <groupId>com.m3</groupId> <artifactId>m3generator</artifactId>
  <version>1.0.0</version>

  <!--Information on the jars this jar depends on-->
  <dependencies>
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
    </dependency>
    ...

repositories {
  maven { // Maven central
    url 'http://central.maven.org/maven2/'    

    content {
      excludeGroup 'com.sun.jmx' //Don't get this group from here
      excludeModule 'jdom', 'jdom' //Don't get this library from here
    }
    //MavenCentral to make the above description()I do not use the abbreviated notation such as
  }