org.neo4j.ogm.exception.MappingException:Error mapping GraphModel to instance of***.ProjectGraph

实例化知识图谱对象ProjectGraph.java 提示如下截图错误信息：

Exception in thread "main" org.neo4j.ogm.exception.MappingException: Error mapping GraphModel to instance of <package>.ProjectGraph at org.neo4j.ogm.context.GraphEntityMapper.mapEntities(GraphEntityMapper.java:145) at org.neo4j.ogm.context.GraphEntityMapper.map(GraphEntityMapper.java:117) at org.neo4j.ogm.context.GraphEntityMapper.map(GraphEntityMapper.java:81) at org.neo4j.ogm.session.delegates.ExecuteQueriesDelegate.executeAndMap(ExecuteQueriesDelegate.java:111) at org.neo4j.ogm.session.delegates.ExecuteQueriesDelegate.query(ExecuteQueriesDelegate.java:82) at org.neo4j.ogm.session.Neo4jSession.query(Neo4jSession.java:323) Caused by: org.neo4j.ogm.exception.MappingException: Unable to instantiate class <package>.ProjectGraph at org.neo4j.ogm.annotations.EntityFactory.instantiate(EntityFactory.java:137) at org.neo4j.ogm.annotations.EntityFactory.instantiateObjectFromTaxa(EntityFactory.java:110) at org.neo4j.ogm.annotations.EntityFactory.newObject(EntityFactory.java:61) at org.neo4j.ogm.context.GraphEntityMapper.mapNodes(GraphEntityMapper.java:156) at org.neo4j.ogm.context.GraphEntityMapper.mapEntities(GraphEntityMapper.java:142) ... 7 more Caused by: java.lang.NoSuchMethodException: <package>.ProjectGraph.<init>() at java.lang.Class.getConstructor0(Class.java:3082) at java.lang.Class.getDeclaredConstructor(Class.java:2178) at org.neo4j.ogm.annotations.EntityFactory.instantiate(EntityFactory.java:133) ... 11 more

造成的原因：ProjectGraph.java 需要没有任何属性的构造函数，补全ProjectGraph 没有任何属性的构造函数。

ProjectGraph.java 错误代码：

import java.util.List; import org.neo4j.ogm.annotation.GraphId; import org.neo4j.ogm.annotation.NodeEntity; import org.neo4j.ogm.annotation.Relationship; /** * 单位工程图谱对象 * * */ @NodeEntity @SuppressWarnings("serial") public class ProjectGraph implements java.io.Serializable{ @GraphId private Long id; private String name; private String sid; @Relationship(type = "IndividualLicenseRelation") private List<LicenseGraph> licenses; @Relationship(type = "IndividualResponRelation") private List<ResponGraph> respons; @Relationship(type = "IndividualUnitRelation") private List<UnitGraph> units; //set 和 get 方法 public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSid() { return sid; } public void setSid(String sid) { this.sid = sid; } public List<LicenseGraph> getLicenses() { return licenses; } public void setLicenses(List<LicenseGraph> licenses) { this.licenses = licenses; } public List<ResponGraph> getRespons() { return respons; } public void setRespons(List<ResponGraph> respons) { this.respons = respons; } public List<UnitGraph> getUnits() { return units; } public void setUnits(List<UnitGraph> units) { this.units = units; } public ProjectGraph(String name, String sid) { this.name = name; this.sid = sid; } }

ProjectGraph.java 修正后的代码：

import java.util.List; import org.neo4j.ogm.annotation.GraphId; import org.neo4j.ogm.annotation.NodeEntity; import org.neo4j.ogm.annotation.Relationship; /** * 单位工程图谱对象 * * */ @NodeEntity @SuppressWarnings("serial") public class ProjectGraph implements java.io.Serializable{ @GraphId private Long id; private String name; private String sid; @Relationship(type = "IndividualLicenseRelation") private List<LicenseGraph> licenses; @Relationship(type = "IndividualResponRelation") private List<ResponGraph> respons; @Relationship(type = "IndividualUnitRelation") private List<UnitGraph> units; //set 和 get 方法 public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getSid() { return sid; } public void setSid(String sid) { this.sid = sid; } public List<LicenseGraph> getLicenses() { return licenses; } public void setLicenses(List<LicenseGraph> licenses) { this.licenses = licenses; } public List<ResponGraph> getRespons() { return respons; } public void setRespons(List<ResponGraph> respons) { this.respons = respons; } public List<UnitGraph> getUnits() { return units; } public void setUnits(List<UnitGraph> units) { this.units = units; } // 构造函数 public ProjectGraph() { super(); } public ProjectGraph(String name, String sid) { this.name = name; this.sid = sid; } }