使用JavaPropsMapper实现properties快速转化
Overview
自接触Properties以来，经常面临一个问题，有没有一个工具能够类似于spring-boot中的 @ConfigurationProperties 一样快速映射一个propertios文件到一个类中，如果没有那么就只能自己撸一个。
调研了一段时间，发现了FasterXML开源项目组里面有一个jackson-dataformats-text项目，这个项目完全满足了这个需求，里面的properties模块包含了如何快速转化一个properties文件到一个类中。
仔细想想，spring-boot中默认的json序列化工具其实用的就是jackson的工具，所以@ConfigurationProperties应该就是根据这个工具来实现的。
JavaPropsMapper
jackson-dataformats-text 是 Jackson（Java）数据格式模块，支持读写 Java Properties 文件，使用命名约定来确定隐含结构，是一个比较灵活的 Java 配置文件读写工具。
Maven dependency
为了能够使用JavaPropsMapper，需要使用如下依赖，这个版本号是在 2019-01 最新的版本
<dependency>
<groupId>com.fasterxml.jackson.dataformat</groupId>
<artifactId>jackson-dataformat-properties</artifactId>
<version>2.9.8</version>
</dependency>
一个例子
以下的例子包含了比较丰富的properties写法，大部分是字符串类型，fabric.orderer.orderers[0]是一个List集合的写法。
fabric.channel.name=mychannel
fabric.chaincode.name=emall_cc
fabric.chaincode.path=github.com/chaincode/emall/go
fabric.chaincode.version=1.0
fabric.orderer.domain-name=example.com
fabric.orderer.orderers[0]=orderer.example.com-grpc://120.78.160.145:7050
fabric.peer.org=org1
fabric.peer.org-name=peerOrg1
fabric.peer.msp-id=Org1MSP
fabric.peer.org-domain-name=org1.example.com
fabric.peer.name=peer0.org1.example.com
fabric.peer.eventhub-name=peer0.org1.example.com
fabric.peer.location=grpc://120.78.160.145:7051
fabric.peer.eventhub-location=grpc://120.78.160.145:7053
fabric.peer.ca-location=http://120.78.160.145:7054
fabric.ca.admin-name=admin
fabric.ca.admin-password=adminpw
同时直接使用在spring-boot中采用@ConfigurationProperties注解的类，去掉注解，但是需要注意使用jackson的注解@JsonProperty去处理那些本应该驼峰式的 index
import java.io.File;
import java.io.IOException;
import java.util.List;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.dataformat.javaprop.JavaPropsMapper;
import com.fasterxml.jackson.dataformat.javaprop.JavaPropsSchema;
@JsonIgnoreProperties(ignoreUnknown = true)
public class FabricProperties {
public static class Channel {
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public String toString() {
return "Channel [name=" + name + "]";
}
}
public static class Chaincode {
private String name;
private String path;
private String version;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPath() {
return path;
}
public void setPath(String path) {
this.path = path;
}
public String getVersion() {
return version;
}
public void setVersion(String version) {
this.version = version;
}
@Override
public String toString() {
return "Chaincode [name=" + name + ", path=" + path + ", version=" + version + "]";
}
}
public static class Orderer {
@JsonProperty("domain-name")
private String domainName;
private List<String> orderers;
public String getDomainName() {
return domainName;
}
public void setDomainName(String domainName) {
this.domainName = domainName;
}
public List<String> getOrderers() {
return orderers;
}
public void setOrderers(List<String> orderers) {
this.orderers = orderers;
}
@Override
public String toString() {
return "Orderer [domainName=" + domainName + ", orderers=" + orderers + "]";
}
}
public static class Peer {
private String org;
@JsonProperty("org-name")
private String orgName;
@JsonProperty("msp-id")
private String mspId;
@JsonProperty("org-domain-name")
private String orgDomainName;
private String name;
@JsonProperty("eventhub-name")
private String eventhubName;
private String location;
@JsonProperty("eventhub-location")
private String eventhubLocation;
@JsonProperty("ca-location")
private String caLocation;
public String getOrg() {
return org;
}
public void setOrg(String org) {
this.org = org;
}
public String getOrgName() {
return orgName;
}
public void setOrgName(String orgName) {
this.orgName = orgName;
}
public String getMspId() {
return mspId;
}
public void setMspId(String mspId) {
this.mspId = mspId;
}
public String getOrgDomainName() {
return orgDomainName;
}
public void setOrgDomainName(String orgDomainName) {
this.orgDomainName = orgDomainName;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEventhubName() {
return eventhubName;
}
public void setEventhubName(String eventhubName) {
this.eventhubName = eventhubName;
}
public String getLocation() {
return location;
}
public void setLocation(String location) {
this.location = location;
}
public String getEventhubLocation() {
return eventhubLocation;
}
public void setEventhubLocation(String eventhubLocation) {
this.eventhubLocation = eventhubLocation;
}
public String getCaLocation() {
return caLocation;
}
public void setCaLocation(String caLocation) {
this.caLocation = caLocation;
}
@Override
public String toString() {
return "Peer [org=" + org + ", orgName=" + orgName + ", mspId=" + mspId + ", orgDomainName=" + orgDomainName
+ ", name=" + name + ", eventhubName=" + eventhubName + ", location=" + location
+ ", eventhubLocation=" + eventhubLocation + ", caLocation=" + caLocation + "]";
}
}
public static class Ca {
@JsonProperty("admin-name")
private String adminName;
@JsonProperty("admin-password")
private String adminPassword;
public String getAdminName() {
return adminName;
}
public void setAdminName(String adminName) {
this.adminName = adminName;
}
public String getAdminPassword() {
return adminPassword;
}
public void setAdminPassword(String adminPassword) {
this.adminPassword = adminPassword;
}
@Override
public String toString() {
return "Ca [adminName=" + adminName + ", adminPassword=" + adminPassword + "]";
}
}
private Channel channel;
private Chaincode chaincode;
private Orderer orderer;
private Peer peer;
private Ca ca;
public Channel getChannel() {
return channel;
}
public void setChannel(Channel channel) {
this.channel = channel;
}
public Chaincode getChaincode() {
return chaincode;
}
public void setChaincode(Chaincode chaincode) {
this.chaincode = chaincode;
}
public Orderer getOrderer() {
return orderer;
}
public void setOrderer(Orderer orderer) {
this.orderer = orderer;
}
public Peer getPeer() {
return peer;
}
public void setPeer(Peer peer) {
this.peer = peer;
}
public Ca getCa() {
return ca;
}
public void setCa(Ca ca) {
this.ca = ca;
}
@Override
public String toString() {
return "FabricProperties [channel=" + channel + ", chaincode=" + chaincode + ", orderer=" + orderer + ", peer="
+ peer + ", ca=" + ca + "]";
}
/**
* 使用jackson提供的JavaPropsMapper实现properties快速解析
* @return
*/
public static FabricProperties load() {
JavaPropsMapper mapper = new JavaPropsMapper();
JavaPropsSchema schema = JavaPropsSchema.emptySchema()
.withoutHeader();
FabricProperties fabric;
try {
fabric = mapper.readerFor(FabricProperties.class)
.with(schema)
.withRootName("fabric")
.readValue(new File(FabricProperties.class.getClassLoader().getResource("fabric.properties").getFile()));
return fabric;
} catch (IOException e) {
e.printStackTrace();
return new FabricProperties();
}
}
}
这边类上面的注解@JsonIgnoreProperties(ignoreUnknown = true)是为了避免在映射的时候出现未知属性的时候出现错误。
最后load()方法便是使用JavaPropsMapper实现properties文件到配置类的映射。
参考
[Blog] Reading/writing Java properties files using Jackson (2.8)
[Issues] Add an option to specify properties prefix
