我通过子类化一个将 Google Guava 作为构造函数参数的类来为 JSimpleDB（一个持久性库）定义一个适配器Converter：
shared class RoleConverter() extends Converter<Role, String>() {
shared actual Role doBackward(String? name) {
"Cannot convert null to role."
assert (exists name);
return Role.ofName(name);
}
shared actual String doForward(Role? role) {
return role?.name else "null";
}
}
shared class RoleType() extends StringEncodedType<Role>(
javaClass<Role>(),
0,
RoleConverter()
) {
}
JSimpleDB 默认不导出 Guava，所以我添加了以下内容overrides.xml以确保正确的类对我的应用程序可见（我没有使用--auto-export-maven-depenciesor --flat-classpath）：
<overrides xmlns="http://www.ceylon-lang.org/xsd/overrides">
<module groupId="org.jsimpledb" artifactId="jsimpledb-coreapi">
<share groupId="com.google.guava" artifactId="guava" />
</module>
<module groupId="org.jsimpledb" artifactId="jsimpledb-main">
<!-- guava is already shared by jsimpledb-coreapi -->
<remove groupId="com.google.guava" artifactId="guava" />
<share groupId="org.jsimpledb" artifactId="jsimpledb-coreapi" />
<share groupId="org.jsimpledb" artifactId="jsimpledb-util" />
<share groupId="org.dellroad" artifactId="dellroad-stuff-main" />
</module>
</overrides>
这导致以下模块层次结构（我的代码在 中fun.uschool.user.impl）：
正确的com.google.guava:guava模块应该暴露给我的程序，确实我可以 import Converter，但是当我尝试编译上面的代码时，我得到以下错误：
source/fun/uschool/user/impl/userImpl.ceylon:156: error: argument must be assignable to parameter 'arg2' of 'StringEncodedType': 'RoleConverter' is not assignable to 'Converter<Role,String>?'
RoleConverter()
^
source/fun/uschool/user/impl/userImpl.ceylon:153: error: Ceylon backend error: no suitable constructor found for StringEncodedType(no arguments)
shared class RoleType() extends StringEncodedType<Role>(
^
constructor StringEncodedType.StringEncodedType(Class<Role>,long,Converter<Role,String>) is not applicable
(actual and formal argument lists differ in length)
constructor StringEncodedType.StringEncodedType(String,Class<Role>,long,Converter<Role,String>) is not applicable
(actual and formal argument lists differ in length)
Note: Created module fun.uschool.feature.spi/1.0.0
Note: Created module fun.uschool.user.api/1.0.0
Note: Created module fun.uschool.feature.impl/1.0.0
Note: Created module fun.uschool.user.impl/1.0.0
ceylon compile: There were 2 errors
所以显然不知何故com.google.guava:guava导入了错误，即使模块依赖关系树中只有 1 个可见。如何导入正确的？
这是ceylon info's 依赖分析的输出：
$ ceylon info fun.uschool.user.impl/1.0.0 --dependency-depth=all
Namespace: ceylon
Name: fun.uschool.user.impl
Version: 1.0.0
Artifacts: JVM (#8.1), Sources
Available: On local system
Origin: /home/ilmoeuro/Asiakirjat/Projektit/youschool/modules
Dependency Tree (up to depth ∞):
ceylon.buffer/1.3.2
ceylon.collection/1.3.2
ceylon.language/1.3.2
ceylon.interop.java/1.3.2
shared ceylon.collection/1.3.2 (already imported)
ceylon.language/1.3.2 (already imported)
shared java.base/7
ceylon.language/1.3.2 (already imported)
java.base/7 (already imported)
ceylon.interop.java/1.3.2 (already imported)
ceylon.language/1.3.2 (already imported)
ceylon.test/1.3.2
ceylon.collection/1.3.2 (already imported)
ceylon.file/1.3.2
ceylon.language/1.3.2 (already imported)
java.base/7 (already imported)
ceylon.language/1.3.2 (already imported)
ceylon.runtime/1.3.2
shared ceylon.language/1.3.2 (already imported)
shared com.redhat.ceylon.cli/1.3.2
shared com.redhat.ceylon.common/1.3.2
shared java.base/7 (already imported)
java.desktop/7
shared java.logging/7
shared com.redhat.ceylon.module-resolver/1.3.2
shared com.redhat.ceylon.common/1.3.2 (already imported)
shared com.redhat.ceylon.langtools.classfile/1.3.2
shared java.base/7 (already imported)
shared com.redhat.ceylon.model/1.3.2
shared com.redhat.ceylon.common/1.3.2 (already imported)
shared com.redhat.ceylon.langtools.classfile/1.3.2 (already imported)
shared java.base/7 (already imported)
shared java.logging/7 (already imported)
optional com.redhat.ceylon.module-resolver-aether/1.3.2
optional com.redhat.ceylon.module-resolver-javascript/1.3.2
optional com.redhat.ceylon.module-resolver-webdav/1.3.2
shared java.base/7 (already imported)
shared java.logging/7 (already imported)
javax.jaxws/7
javax.script/7
shared javax.xml/7
shared java.base/7 (already imported)
java.desktop/7 (already imported)
shared java.logging/7 (already imported)
shared optional org.tautua.markdownpapers.core/1.2.7
shared com.redhat.ceylon.common/1.3.2 (already imported)
shared com.redhat.ceylon.model/1.3.2 (already imported)
shared com.redhat.ceylon.module-resolver/1.3.2 (already imported)
com.redhat.ceylon.tool.provider/1.3.2
ceylon.language/1.3.2 (already imported)
shared com.redhat.ceylon.cli/1.3.2 (already imported)
shared com.redhat.ceylon.common/1.3.2 (already imported)
shared com.redhat.ceylon.compiler.java/1.3.2
ceylon.language/1.3.2 (already imported)
com.github.rjeschke.txtmark/0.13
shared java.base/7 (already imported)
shared com.redhat.ceylon.cli/1.3.2 (already imported)
shared com.redhat.ceylon.common/1.3.2 (already imported)
shared com.redhat.ceylon.langtools.classfile/1.3.2 (already imported)
shared com.redhat.ceylon.model/1.3.2 (already imported)
shared com.redhat.ceylon.module-resolver/1.3.2 (already imported)
shared com.redhat.ceylon.typechecker/1.3.2
shared com.redhat.ceylon.common/1.3.2 (already imported)
shared com.redhat.ceylon.model/1.3.2 (already imported)
shared com.redhat.ceylon.module-resolver/1.3.2 (already imported)
shared java.base/7 (already imported)
shared org.antlr.runtime/3.4
shared java.base/7 (already imported)
shared org.antlr.stringtemplate/3.2.1
shared java.base/7 (already imported)
shared java.desktop/7 (already imported)
shared org.antlr.antlr/2.7.7
shared java.base/7 (already imported)
shared java.desktop/7 (already imported)
shared java.base/7 (already imported)
shared java.compiler/7
java.desktop/7 (already imported)
java.logging/7 (already imported)
java.prefs/7
shared javax.xml/7 (already imported)
oracle.jdk.base/7
shared org.antlr.runtime/3.4 (already imported)
com.redhat.ceylon.compiler.js/1.3.2
ceylon.language/1.3.2 (already imported)
shared com.redhat.ceylon.cli/1.3.2 (already imported)
shared com.redhat.ceylon.common/1.3.2 (already imported)
shared com.redhat.ceylon.model/1.3.2 (already imported)
shared com.redhat.ceylon.module-resolver/1.3.2 (already imported)
com.redhat.ceylon.module-resolver-javascript/1.3.2
net.minidev.json-smart/1.1.1
shared java.base/7 (already imported)
shared com.redhat.ceylon.typechecker/1.3.2 (already imported)
shared java.base/7 (already imported)
shared java.logging/7 (already imported)
net.minidev.json-smart/1.1.1 (already imported)
shared org.antlr.runtime/3.4 (already imported)
com.redhat.ceylon.model/1.3.2 (already imported)
com.redhat.ceylon.module-loader/1.3.2
ceylon.language/1.3.2 (already imported)
com.redhat.ceylon.common/1.3.2 (already imported)
com.redhat.ceylon.model/1.3.2 (already imported)
shared com.redhat.ceylon.module-resolver/1.3.2 (already imported)
shared java.base/7 (already imported)
optional org.jboss.modules/1.4.4.Final
shared com.redhat.ceylon.module-resolver/1.3.2 (already imported)
com.redhat.ceylon.typechecker/1.3.2 (already imported)
shared java.base/7 (already imported)
org.jboss.modules/1.4.4.Final
shared java.base/7 (already imported)
shared java.instrument/7
shared java.logging/7 (already imported)
java.management/7
java.prefs/7 (already imported)
shared javax.xml/7 (already imported)
oracle.jdk.base/7 (already imported)
shared java.base/7 (already imported)
java.compiler/7 (already imported)
shared java.instrument/7 (already imported)
javax.xml/7 (already imported)
org.jboss.logmanager/2.0.3.Final
shared java.base/7 (already imported)
shared java.logging/7 (already imported)
java.management/7 (already imported)
shared java.tls/7
optional org.jboss.modules/1.4.4.Final
shared org.jboss.modules/1.4.4.Final (already imported)
java.base/7 (already imported)
org.jboss.modules/1.4.4.Final (already imported)
shared fun.uschool.feature.impl/1.0.0
ceylon.buffer/1.3.2 (already imported)
ceylon.interop.java/1.3.2 (already imported)
ceylon.language/1.3.2 (already imported)
shared maven:com.moandjiezana.toml:toml4j/0.7.1
maven:com.google.code.gson:gson/2.3.1
shared fun.uschool.feature.spi/1.0.0
ceylon.language/1.3.2 (already imported)
shared java.base/8 (already imported other version)
shared maven:org.jsimpledb:jsimpledb-main/3.5.0
maven:com.google.code.findbugs:jsr305/3.0.1 PROVIDED
maven:javax.el:javax.el-api/2.2.5
maven:javax.validation:validation-api/1.1.0.Final
maven:log4j:log4j/1.2.17 RUNTIME
optional maven:javax.mail:mail/1.4.3
optional maven:org.apache.geronimo.specs:geronimo-jms_1.1_spec/1.0
maven:org.apache.openejb:javaee-api/5.0-2 PROVIDED
maven:org.dellroad:dellroad-stuff-main/2.1.0
optional maven:au.com.bytecode:opencsv/2.4
maven:com.google.guava:guava/21.0
optional maven:com.google.code.findbugs:jsr305/1.3.9
optional maven:com.google.errorprone:error_prone_annotations/2.0.15
optional maven:com.google.j2objc:j2objc-annotations/1.1
optional maven:org.codehaus.mojo:animal-sniffer-annotations/1.14
maven:javax.validation:validation-api/1.1.0.Final (already imported)
optional maven:jline:jline/2.14.2
optional maven:log4j:log4j/1.2.17
optional maven:org.apache.ant:ant/1.9.7
optional maven:org.hibernate.javax.persistence:hibernate-jpa-2.1-api/1.0.0.Final
optional maven:org.hibernate:hibernate-core/5.0.7.Final
maven:org.slf4j:slf4j-api/1.7.25
maven:org.slf4j:slf4j-log4j12/1.7.25 RUNTIME
maven:log4j:log4j/1.2.17 (already imported)
maven:org.slf4j:slf4j-api/1.7.25 (already imported)
optional maven:org.springframework:spring-context/4.3.7.RELEASE
maven:org.hibernate:hibernate-validator/5.2.4.Final
maven:com.fasterxml:classmate/1.1.0
optional maven:com.thoughtworks.paranamer:paranamer/2.5.5
maven:javax.el:javax.el-api/2.2.4 PROVIDED (already imported other version)
maven:javax.validation:validation-api/1.1.0.Final (already imported)
optional maven:joda-time:joda-time/2.7
maven:org.glassfish.web:javax.el/2.2.4 PROVIDED
maven:javax.el:javax.el-api/2.2.4 (already imported other version)
optional maven:org.hibernate.javax.persistence:hibernate-jpa-2.1-api/1.0.0.Final
maven:org.jboss.logging:jboss-logging/3.2.1.Final
maven:log4j:log4j/1.2.16 PROVIDED (already imported other version)
maven:org.apache.logging.log4j:log4j-api/2.0 PROVIDED
maven:org.osgi:org.osgi.core/4.3.1 PROVIDED
maven:org.jboss.logmanager:jboss-logmanager/1.5.2.Final PROVIDED
optional maven:org.jboss.modules:jboss-modules/1.1.0.GA PROVIDED
maven:org.slf4j:slf4j-api/1.7.2 PROVIDED (already imported other version)
maven:org.jboss.logging:jboss-logging-processor/1.2.0.Final PROVIDED
maven:org.jboss.jdeparser:jdeparser/1.0.0.Final
maven:org.jboss.logging:jboss-logging/3.1.2.GA PROVIDED (already imported other version)
maven:org.jboss.logging:jboss-logging-annotations/1.2.0.Final
maven:org.jboss.logging:jboss-logging/3.1.2.GA PROVIDED (already imported other version)
optional maven:org.jsoup:jsoup/1.8.3
shared maven:org.jsimpledb:jsimpledb-coreapi/3.5.0
maven:com.google.code.findbugs:jsr305/3.0.1 PROVIDED (already imported)
maven:commons-codec:commons-codec/1.10
maven:log4j:log4j/1.2.17 RUNTIME (already imported other version)
maven:org.dellroad:dellroad-stuff-main/2.1.0 (already imported)
maven:org.jsimpledb:jsimpledb-kv/3.5.0
maven:com.google.code.findbugs:jsr305/3.0.1 PROVIDED (already imported)
maven:com.google.guava:guava/21.0 (already imported)
maven:log4j:log4j/1.2.17 RUNTIME (already imported other version)
maven:org.dellroad:dellroad-stuff-main/2.1.0 (already imported)
maven:org.jsimpledb:jsimpledb-util/3.5.0
maven:com.google.code.findbugs:jsr305/3.0.1 PROVIDED (already imported)
shared maven:com.google.guava:guava/21.0 (already imported)
maven:log4j:log4j/1.2.17 RUNTIME (already imported other version)
maven:org.slf4j:slf4j-api/1.7.25 (already imported other version)
maven:org.slf4j:slf4j-log4j12/1.7.25 RUNTIME (already imported)
maven:org.slf4j:slf4j-api/1.7.25 (already imported other version)
maven:org.slf4j:slf4j-log4j12/1.7.25 RUNTIME (already imported)
shared maven:org.jsimpledb:jsimpledb-util/3.5.0 (already imported)
maven:org.slf4j:slf4j-api/1.7.25 (already imported other version)
maven:org.slf4j:slf4j-log4j12/1.7.25 RUNTIME (already imported)
maven:org.jsimpledb:jsimpledb-kv/3.5.0 (already imported)
maven:org.jsimpledb:jsimpledb-kv-simple/3.5.0
maven:com.google.code.findbugs:jsr305/3.0.1 PROVIDED (already imported)
maven:com.google.guava:guava/21.0 (already imported)
maven:log4j:log4j/1.2.17 RUNTIME (already imported other version)
maven:org.dellroad:dellroad-stuff-main/2.1.0 (already imported)
maven:org.jsimpledb:jsimpledb-kv/3.5.0 (already imported)
maven:org.jsimpledb:jsimpledb-util/3.5.0 (already imported)
maven:org.slf4j:slf4j-api/1.7.25 (already imported other version)
maven:org.slf4j:slf4j-log4j12/1.7.25 RUNTIME (already imported)
maven:org.slf4j:slf4j-api/1.7.25 (already imported other version)
maven:org.slf4j:slf4j-log4j12/1.7.25 RUNTIME (already imported)
shared fun.uschool.feature.spi/1.0.0 (already imported)
shared fun.uschool.user.api/1.0.0
ceylon.language/1.3.2 (already imported)
shared fun.uschool.feature.spi/1.0.0 (already imported)
fun.uschool.user.impl/1.0.0
ceylon.buffer/1.3.2 (already imported)
ceylon.interop.java/1.3.2 (already imported)
ceylon.language/1.3.2 (already imported)
ceylon.test/1.3.2 (already imported)
shared fun.uschool.feature.impl/1.0.0 (already imported)
shared fun.uschool.feature.spi/1.0.0 (already imported)
shared fun.uschool.user.api/1.0.0 (already imported)
shared java.base/8 (already imported other version)
shared java.base/8 (already imported other version)
Dependencies (up to depth ∞):
ceylon.buffer/1.3.2
ceylon.collection/1.3.2
ceylon.file/1.3.2
ceylon.interop.java/1.3.2
ceylon.language/1.3.2
ceylon.runtime/1.3.2
ceylon.test/1.3.2
com.fasterxml:classmate/1.1.0
com.github.rjeschke.txtmark/0.13
com.google.code.findbugs:jsr305/3.0.1
com.google.code.gson:gson/2.3.1
com.google.guava:guava/21.0
com.moandjiezana.toml:toml4j/0.7.1
com.redhat.ceylon.cli/1.3.2
com.redhat.ceylon.common/1.3.2
com.redhat.ceylon.compiler.java/1.3.2
com.redhat.ceylon.compiler.js/1.3.2
com.redhat.ceylon.langtools.classfile/1.3.2
com.redhat.ceylon.model/1.3.2
com.redhat.ceylon.module-loader/1.3.2
com.redhat.ceylon.module-resolver/1.3.2
com.redhat.ceylon.module-resolver-javascript/1.3.2
com.redhat.ceylon.tool.provider/1.3.2
com.redhat.ceylon.typechecker/1.3.2
commons-codec:commons-codec/1.10
fun.uschool.feature.impl/1.0.0
fun.uschool.feature.spi/1.0.0
fun.uschool.user.api/1.0.0
fun.uschool.user.impl/1.0.0
java.base: 7, 8
java.compiler/7
java.desktop/7
java.instrument/7
java.logging/7
java.management/7
java.prefs/7
java.tls/7
javax.el:javax.el-api: 2.2.4, 2.2.5
javax.jaxws/7
javax.script/7
javax.validation:validation-api/1.1.0.Final
javax.xml/7
log4j:log4j: 1.2.16, 1.2.17
net.minidev.json-smart/1.1.1
oracle.jdk.base/7
org.antlr.antlr/2.7.7
org.antlr.runtime/3.4
org.antlr.stringtemplate/3.2.1
org.apache.logging.log4j:log4j-api/2.0
org.apache.openejb:javaee-api/5.0-2
org.dellroad:dellroad-stuff-main/2.1.0
org.glassfish.web:javax.el/2.2.4
org.hibernate:hibernate-validator/5.2.4.Final
org.jboss.jdeparser:jdeparser/1.0.0.Final
org.jboss.logging:jboss-logging: 3.1.2.GA, 3.2.1.Final
org.jboss.logging:jboss-logging-annotations/1.2.0.Final
org.jboss.logging:jboss-logging-processor/1.2.0.Final
org.jboss.logmanager/2.0.3.Final
org.jboss.logmanager:jboss-logmanager/1.5.2.Final
org.jboss.modules/1.4.4.Final
org.jsimpledb:jsimpledb-coreapi/3.5.0
org.jsimpledb:jsimpledb-kv/3.5.0
org.jsimpledb:jsimpledb-kv-simple/3.5.0
org.jsimpledb:jsimpledb-main/3.5.0
org.jsimpledb:jsimpledb-util/3.5.0
org.osgi:org.osgi.core/4.3.1
org.slf4j:slf4j-api: 1.7.2, 1.7.25
org.slf4j:slf4j-log4j12/1.7.25
Dependencies version conflicts (up to depth ∞):
java.base: 7, 8
javax.el:javax.el-api: 2.2.4, 2.2.5
log4j:log4j: 1.2.16, 1.2.17
org.jboss.logging:jboss-logging: 3.1.2.GA, 3.2.1.Final
org.slf4j:slf4j-api: 1.7.2, 1.7.25